Heatmap chart

A grid of values shaded from low to high. Use it for two categories against one measure, such as weekday against hour. The scale is one chart colour mixed into the surface, so it follows light and dark themes. Hover, touch or arrow-key to a cell to read it.

Sessions by weekday and hour

Darker cells are busier. Hover a cell, or focus the grid and use the arrow keys.

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Sessions by weekday and hour of day
Row	9	10	11	12	13	14	15	16
Mon	12	24	31	18	9	22	27	14
Tue	15	29	36	21	11	26	33	17
Wed	14	27	40	25	13	30	35	19
Thu	11	23	33	19	–	24	29	13
Fri	8	16	21	12	6	10	12	5

Server load through 2026

Requests per second, by hour of day. 8,760 cells drawn on a canvas.

Requests per second by hour and day (first 21 of 24 rows)
Row	1 Jan	2 Jan	3 Jan	4 Jan	5 Jan	6 Jan	7 Jan	8 Jan	9 Jan	10 Jan	11 Jan	12 Jan	13 Jan	14 Jan	15 Jan	16 Jan	17 Jan	18 Jan	19 Jan	20 Jan	21 Jan	22 Jan	23 Jan	24 Jan	25 Jan	26 Jan	27 Jan	28 Jan	29 Jan	30 Jan	31 Jan	1 Feb	2 Feb	3 Feb	4 Feb	5 Feb	6 Feb	7 Feb	8 Feb	9 Feb	10 Feb	11 Feb	12 Feb	13 Feb	14 Feb	15 Feb	16 Feb	17 Feb	18 Feb	19 Feb	20 Feb	21 Feb	22 Feb	23 Feb	24 Feb	25 Feb	26 Feb	27 Feb	28 Feb	1 Mar	2 Mar	3 Mar	4 Mar	5 Mar	6 Mar	7 Mar	8 Mar	9 Mar	10 Mar	11 Mar	12 Mar	13 Mar	14 Mar	15 Mar	16 Mar	17 Mar	18 Mar	19 Mar	20 Mar	21 Mar	22 Mar	23 Mar	24 Mar	25 Mar	26 Mar	27 Mar	28 Mar	29 Mar	30 Mar	31 Mar	1 Apr	2 Apr	3 Apr	4 Apr	5 Apr	6 Apr	7 Apr	8 Apr	9 Apr	10 Apr	11 Apr	12 Apr	13 Apr	14 Apr	15 Apr	16 Apr	17 Apr	18 Apr	19 Apr	20 Apr	21 Apr	22 Apr	23 Apr	24 Apr	25 Apr	26 Apr	27 Apr	28 Apr	29 Apr	30 Apr	1 May	2 May	3 May	4 May	5 May	6 May	7 May	8 May	9 May	10 May	11 May	12 May	13 May	14 May	15 May	16 May	17 May	18 May	19 May	20 May	21 May	22 May	23 May	24 May	25 May	26 May	27 May	28 May	29 May	30 May	31 May	1 Jun	2 Jun	3 Jun	4 Jun	5 Jun	6 Jun	7 Jun	8 Jun	9 Jun	10 Jun	11 Jun	12 Jun	13 Jun	14 Jun	15 Jun	16 Jun	17 Jun	18 Jun	19 Jun	20 Jun	21 Jun	22 Jun	23 Jun	24 Jun	25 Jun	26 Jun	27 Jun	28 Jun	29 Jun	30 Jun	1 Jul	2 Jul	3 Jul	4 Jul	5 Jul	6 Jul	7 Jul	8 Jul	9 Jul	10 Jul	11 Jul	12 Jul	13 Jul	14 Jul	15 Jul	16 Jul	17 Jul	18 Jul	19 Jul	20 Jul	21 Jul	22 Jul	23 Jul	24 Jul	25 Jul	26 Jul	27 Jul	28 Jul	29 Jul	30 Jul	31 Jul	1 Aug	2 Aug	3 Aug	4 Aug	5 Aug	6 Aug	7 Aug	8 Aug	9 Aug	10 Aug	11 Aug	12 Aug	13 Aug	14 Aug	15 Aug	16 Aug	17 Aug	18 Aug	19 Aug	20 Aug	21 Aug	22 Aug	23 Aug	24 Aug	25 Aug	26 Aug	27 Aug	28 Aug	29 Aug	30 Aug	31 Aug	1 Sep	2 Sep	3 Sep	4 Sep	5 Sep	6 Sep	7 Sep	8 Sep	9 Sep	10 Sep	11 Sep	12 Sep	13 Sep	14 Sep	15 Sep	16 Sep	17 Sep	18 Sep	19 Sep	20 Sep	21 Sep	22 Sep	23 Sep	24 Sep	25 Sep	26 Sep	27 Sep	28 Sep	29 Sep	30 Sep	1 Oct	2 Oct	3 Oct	4 Oct	5 Oct	6 Oct	7 Oct	8 Oct	9 Oct	10 Oct	11 Oct	12 Oct	13 Oct	14 Oct	15 Oct	16 Oct	17 Oct	18 Oct	19 Oct	20 Oct	21 Oct	22 Oct	23 Oct	24 Oct	25 Oct	26 Oct	27 Oct	28 Oct	29 Oct	30 Oct	31 Oct	1 Nov	2 Nov	3 Nov	4 Nov	5 Nov	6 Nov	7 Nov	8 Nov	9 Nov	10 Nov	11 Nov	12 Nov	13 Nov	14 Nov	15 Nov	16 Nov	17 Nov	18 Nov	19 Nov	20 Nov	21 Nov	22 Nov	23 Nov	24 Nov	25 Nov	26 Nov	27 Nov	28 Nov	29 Nov	30 Nov	1 Dec	2 Dec	3 Dec	4 Dec	5 Dec	6 Dec	7 Dec	8 Dec	9 Dec	10 Dec	11 Dec	12 Dec	13 Dec	14 Dec	15 Dec	16 Dec	17 Dec	18 Dec	19 Dec	20 Dec	21 Dec	22 Dec	23 Dec	24 Dec	25 Dec	26 Dec	27 Dec	28 Dec	29 Dec	30 Dec	31 Dec
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02:00	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20
03:00	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20
04:00	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	21	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	21	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20	20
05:00	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	20	21	21	21	21	22	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	20	21	21	21	21	21	21	21	21	21	21	21	21	21	21	20	21	21	21	21	21	21	20	21	21	21	21	21	20	21	21	21	21	21	21	20	20	21	21	21	21	21	20	21	21	21	21	21	21	20	20	21	21	21	21	21	20	20	21	21	21	21	21	21	20	21	21	21	21	21	20	20	21	21	20	21	21	20	20	21	21	21	21	21	20	20	20	21	21	21	21	20	20	21	21	21	21	20	20	20	20	21	21	20	21	20	20	20	21	21	21	21	20	20	21	21	21	21	21	20	20	21	21	21	21	21	20	20	21	21	21	21	21	20	20	21	21	21	20	21	20	20	21	21	21	21	21	20	20	21	21	21	21	21	20	20	21	21	21	21	21	20	20	21	21	21	21	21	21	20	21	21	21	21	20	20	20	21	21	21	21	21	20	20	21	21	21	21	21	20	20	21	21	21	21	21	20	20	21	21	21	21	21	20	20	21	21	21	21	21	21	21	21	21	21	21	21	21	20	21	21	21	21	21	20	20	21	21	21	21	21	20	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	20	21	21	21	21	21	21	21	21	21	22	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21	21
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07:00	27	27	23	23	26	28	28	27	27	24	24	26	29	26	27	28	24	24	25	27	28	25	28	24	24	27	27	28	24	27	22	23	27	26	27	26	26	24	23	27	25	25	25	27	23	24	26	26	27	27	27	24	24	26	27	27	27	25	23	23	27	26	25	26	25	23	23	26	26	27	26	27	23	24	26	26	26	26	26	24	23	26	27	25	25	26	24	23	24	25	25	26	26	23	23	26	26	25	25	26	23	23	26	25	25	25	24	23	22	24	25	24	25	25	23	23	24	24	25	23	24	23	23	25	25	25	24	24	22	23	24	24	25	24	25	22	23	25	23	23	24	24	22	23	24	24	24	24	24	22	22	23	24	24	24	23	22	22	23	24	23	24	24	22	22	24	23	24	24	24	21	22	24	23	22	24	24	22	22	23	24	23	24	23	22	22	24	24	23	24	24	22	22	23	24	23	24	24	23	22	24	23	24	24	23	22	22	24	24	24	22	24	22	22	24	24	24	25	24	22	22	24	25	24	24	25	22	22	24	23	25	23	23	22	23	24	24	24	24	25	22	22	24	25	25	24	26	22	22	25	26	25	24	24	22	22	25	24	24	25	26	23	22	24	25	25	25	26	23	22	25	25	25	25	26	23	23	25	25	25	26	26	24	23	25	26	26	26	26	23	23	25	24	26	26	26	24	24	26	27	27	27	26	24	23	25	26	26	27	26	23	24	26	29	28	26	25	24	25	27	28	24	26	26	24	24	26	26	28	25	28	25	24	26	26	27	28	26	23	23	28	27	28	28	27	23	25	26	28	28	27	26	24	23	24	26	27	26	27	24	24	27	27	27	27
08:00	35	33	27	26	33	36	36	34	32	28	29	37	33	36	34	36	28	27	34	34	32	35	36	27	28	36	31	32	33	33	29	26	35	29	33	34	36	26	27	35	34	35	32	37	28	27	36	33	34	35	33	28	26	32	31	36	33	35	28	28	32	33	31	34	34	25	27	33	29	33	33	29	26	27	33	33	35	31	31	27	28	29	29	32	30	30	27	25	31	31	30	31	30	28	24	29	32	30	30	31	24	26	29	33	30	32	29	25	25	33	32	32	30	32	25	25	30	31	28	30	30	24	25	28	30	31	27	29	25	23	32	29	29	28	29	25	25	29	27	27	31	29	24	25	28	29	28	28	29	24	24	27	28	27	30	29	25	26	28	29	26	29	27	26	23	25	28	28	28	29	24	24	29	27	28	27	29	24	25	28	26	26	27	27	24	23	28	30	29	28	28	25	25	27	27	27	27	28	24	24	28	26	26	27	29	25	25	27	27	28	26	29	25	25	27	28	29	29	28	26	25	28	29	28	26	30	25	24	27	28	27	30	26	25	24	29	30	28	28	27	25	24	27	27	31	30	30	25	26	35	30	30	27	32	26	25	31	30	30	29	28	25	25	31	29	28	29	33	26	27	29	30	32	32	29	27	26	30	32	30	34	29	24	27	33	31	31	30	31	25	26	32	31	29	29	33	27	27	30	33	32	32	32	27	25	30	32	32	31	31	27	28	31	34	30	34	33	27	29	30	34	33	31	31	26	27	34	32	34	34	35	28	29	37	33	33	30	35	28	27	34	35	35	34	31	26	29	31	35	34	32	32	29	30	37	34	35	36	34	26	27	34	34	35	36
09:00	40	42	30	34	42	52	52	45	43	36	34	48	49	42	48	44	29	38	49	43	50	41	43	35	32	45	45	39	47	46	34	35	44	47	47	43	42	34	33	44	39	43	49	45	32	36	39	42	46	43	46	33	32	34	42	48	40	45	32	33	40	55	40	42	42	31	31	40	42	45	43	42	34	34	33	39	41	41	41	33	32	46	37	37	39	43	34	32	43	41	40	34	43	29	31	39	40	41	41	40	30	31	38	42	40	32	40	32	30	37	35	37	37	35	30	31	37	40	37	41	36	28	30	36	41	34	34	36	27	26	35	36	35	39	37	28	26	34	37	34	36	39	30	29	35	35	34	35	31	28	28	32	35	36	31	36	29	26	35	34	33	36	36	27	27	37	32	34	32	35	26	27	34	37	33	34	33	28	28	34	34	34	36	33	29	28	31	34	35	35	38	28	26	33	34	35	36	39	26	27	35	35	37	35	33	28	29	36	38	34	36	35	26	29	38	37	33	37	33	28	27	38	32	34	40	34	28	30	36	38	38	33	38	30	29	36	37	37	35	36	30	26	38	36	38	39	38	30	30	36	38	36	39	38	29	31	39	36	34	40	33	27	32	44	41	40	43	38	34	31	37	39	41	38	38	34	30	40	42	45	41	40	31	32	36	42	39	39	38	30	35	41	42	40	40	43	33	34	44	42	43	44	46	33	34	47	47	43	37	37	33	34	40	41	43	40	51	33	32	48	43	41	43	44	34	35	42	52	53	44	42	31	38	39	49	39	44	41	37	36	39	46	50	49	51	31	36	41	49	43	50	45	35	33	48	51	49	47	43	36	34	43	50	45	42
10:00	56	60	41	39	70	68	60	65	57	41	42	56	61	56	74	62	42	48	59	51	58	68	61	40	41	60	69	60	66	68	46	43	64	61	60	53	66	40	37	51	58	61	64	66	43	47	60	45	56	57	56	39	39	57	55	62	62	60	39	37	57	47	49	56	59	37	43	59	64	59	47	61	40	36	56	52	53	53	52	41	40	52	57	46	53	51	39	40	57	48	52	48	51	40	31	50	53	51	48	48	35	39	49	55	52	50	47	41	37	46	40	52	53	46	30	36	54	42	39	45	51	33	38	46	52	53	53	48	37	38	48	49	42	48	51	32	36	50	39	39	48	38	35	35	47	45	42	45	48	31	34	44	50	47	43	41	29	34	44	47	43	43	46	35	31	42	43	41	48	42	34	34	35	40	42	39	37	30	29	43	41	33	45	42	32	34	45	37	47	43	48	30	34	44	44	48	42	47	30	30	49	45	46	42	45	34	27	41	48	46	44	44	33	34	55	48	43	44	46	29	31	44	40	39	49	46	36	35	40	47	46	44	46	33	35	46	46	46	45	55	35	38	49	49	51	50	43	36	35	55	52	50	56	46	37	38	54	49	53	50	52	39	37	51	50	58	54	49	37	34	48	53	59	54	56	43	36	52	50	52	61	57	42	41	53	42	49	55	65	41	42	58	57	55	61	69	37	40	69	51	58	52	59	41	41	60	56	60	57	56	41	45	55	61	45	55	63	46	48	59	65	67	59	57	44	42	54	65	63	63	55	43	47	67	70	55	59	57	43	45	62	64	69	59	63	44	50	61	59	57	56	68	41	43	71	47	72	64	46	44	42	77	56	63	64
11:00	86	99	51	52	92	57	99	84	78	54	56	112	72	81	71	99	47	55	82	88	70	101	86	55	57	94	70	79	82	78	54	52	84	88	84	96	72	59	48	89	65	92	78	83	57	45	74	67	80	87	81	62	49	82	85	69	79	83	45	55	85	70	89	88	78	45	53	100	79	81	65	75	51	53	71	69	69	74	80	45	46	58	76	72	73	72	40	36	80	65	74	66	61	44	42	74	71	65	72	77	44	41	68	73	68	58	61	40	42	69	63	60	56	72	44	47	64	62	45	65	68	45	40	63	60	46	50	55	44	44	64	67	53	56	65	39	38	54	64	60	50	60	40	42	61	52	58	56	59	40	40	59	62	57	61	60	34	33	46	57	54	64	56	36	35	60	47	59	61	55	42	40	50	60	48	55	61	42	36	46	59	55	53	44	33	36	50	59	53	51	60	43	44	47	52	53	55	44	39	40	54	62	49	49	52	40	39	52	59	59	52	51	38	38	72	57	57	48	63	29	39	63	62	54	62	50	46	42	52	64	57	62	45	44	42	54	52	56	53	63	43	43	58	62	47	55	63	37	40	64	59	77	60	69	47	44	64	69	65	73	53	42	40	64	54	69	72	68	50	49	65	63	72	66	74	45	47	54	92	79	71	66	46	46	66	75	80	68	77	56	47	71	68	67	62	80	45	51	71	54	53	80	83	48	48	78	76	64	71	77	48	57	82	84	71	90	96	57	55	78	63	72	84	95	48	59	90	90	65	89	79	54	62	78	84	76	86	100	59	52	86	66	82	81	89	63	48	75	95	91	76	87	54	58	88	70	106	95	69	53	53	74	80	79	92
12:00	122	101	63	56	98	105	102	103	116	67	52	121	92	131	107	126	61	64	95	94	108	101	104	57	67	118	102	105	109	118	50	61	101	78	85	91	112	66	59	98	106	83	121	106	60	47	119	91	95	73	91	62	60	85	89	107	97	107	54	70	79	123	83	107	93	59	66	95	77	109	92	95	47	62	97	83	96	104	96	54	62	89	79	93	107	84	60	54	76	83	82	92	71	53	61	78	89	90	86	93	58	52	86	76	77	75	87	54	54	78	77	68	72	79	55	51	58	68	62	64	75	47	51	78	70	72	71	68	46	47	73	65	68	78	75	39	53	75	80	79	60	65	53	46	70	75	69	77	71	48	45	68	70	63	64	70	45	44	67	70	74	64	69	49	45	69	74	64	66	66	46	42	64	70	59	66	73	45	47	58	57	75	78	55	40	38	58	68	71	66	66	44	46	64	70	72	63	62	44	50	70	62	61	62	71	43	40	64	61	59	62	67	41	51	72	78	66	63	79	49	53	59	55	69	79	74	53	48	72	67	62	77	71	50	52	73	73	84	74	81	50	48	65	69	70	92	79	51	50	79	85	75	75	83	55	61	64	69	89	84	85	49	50	90	78	94	84	93	49	49	80	84	87	87	80	51	54	73	93	78	81	88	46	65	64	105	68	103	74	51	55	85	89	95	85	107	65	70	100	64	92	93	129	63	60	74	75	93	87	94	59	62	104	92	91	110	111	59	61	75	89	96	113	94	53	58	102	104	95	91	106	54	59	75	122	76	109	103	72	63	96	121	116	79	97	60	68	109	94	100	93	98	62	53	108	105	100	114	102	54	69	120	107	94	108
13:00	145	149	64	73	122	85	103	120	105	69	69	104	97	123	130	124	64	68	123	137	131	149	96	82	60	109	126	115	105	121	88	64	98	107	102	119	114	81	75	125	111	120	122	105	62	75	118	120	109	102	131	70	76	137	99	99	100	127	58	69	107	120	105	105	119	66	71	106	137	121	119	107	57	74	110	102	115	98	99	55	73	112	82	81	73	84	70	65	109	86	82	94	85	57	58	99	111	87	88	100	69	71	82	72	93	92	95	57	60	94	87	97	88	96	61	64	96	83	78	87	85	51	55	76	72	82	80	95	47	52	82	86	93	71	77	49	64	62	86	68	69	81	50	49	84	76	82	76	82	53	47	71	71	95	58	70	54	44	71	70	67	67	65	40	52	73	71	77	72	63	53	51	70	78	69	64	92	42	48	78	69	74	72	73	48	51	76	80	69	66	67	52	51	80	73	75	73	73	45	49	70	62	83	70	77	46	54	83	69	65	91	74	53	48	69	74	84	80	66	51	47	87	90	76	78	77	45	60	81	84	82	86	94	58	60	83	86	83	72	91	66	55	102	90	93	83	74	66	58	67	89	76	78	85	61	55	93	101	114	82	75	53	51	78	95	90	84	84	68	71	94	112	102	100	100	68	65	78	93	96	92	98	53	65	106	90	82	85	99	60	63	115	104	113	106	102	60	59	110	108	111	132	122	66	58	107	93	112	94	96	63	66	102	108	95	88	99	75	55	102	126	113	105	114	80	87	100	91	118	128	120	87	71	116	127	114	105	119	73	77	144	118	110	117	126	88	77	126	122	110	112	99	70	68	109	128	108	127	106	58	82	132	110	125	105
14:00	139	100	84	76	130	130	102	116	142	81	67	123	155	135	135	133	74	82	142	136	145	124	114	86	80	118	118	129	125	149	72	84	82	132	120	128	139	59	80	77	140	129	117	93	66	93	137	128	135	132	117	75	79	112	108	96	119	138	63	74	124	141	129	102	115	73	79	119	120	125	103	105	62	57	104	89	116	109	123	69	54	109	117	98	67	99	67	67	103	104	92	89	107	64	61	79	102	106	113	91	71	59	75	94	120	88	94	59	60	110	101	107	84	99	67	55	110	86	100	85	72	56	55	72	85	83	85	80	59	52	113	87	93	94	89	52	51	85	83	81	65	91	52	56	92	81	69	77	88	51	53	64	65	78	71	71	58	53	84	77	76	82	90	50	54	83	78	81	63	78	57	53	82	69	68	70	68	50	54	69	72	84	90	81	51	47	64	79	72	70	85	47	47	70	89	67	86	85	58	51	77	54	66	74	64	47	59	85	73	67	90	86	57	57	90	71	63	68	93	55	55	62	87	85	95	98	56	63	85	86	95	85	90	61	59	89	86	84	67	98	52	59	95	105	90	101	92	59	70	103	99	93	87	106	61	63	85	106	88	84	85	64	58	95	115	100	107	97	65	71	98	103	90	100	86	66	62	103	101	123	90	108	72	70	115	82	118	106	97	79	56	95	87	98	92	106	63	60	78	104	90	103	93	65	61	101	122	109	104	108	69	62	114	111	109	114	93	60	56	115	108	111	110	115	69	78	107	121	126	102	131	76	81	155	153	105	128	121	71	72	127	119	148	109	121	81	80	121	120	125	124	102	72	89	114	128	127	132	122	70	64	130	128	118	126
15:00	107	127	78	89	81	102	122	125	112	73	52	122	127	125	110	104	67	74	139	134	113	132	110	84	68	78	102	110	110	144	74	77	108	103	130	135	106	77	77	117	82	99	119	120	76	71	142	121	116	109	104	69	62	119	120	139	110	115	73	68	105	114	110	110	106	66	64	108	86	104	121	108	65	76	122	112	110	111	115	61	66	97	109	104	92	99	56	60	105	108	94	94	106	63	58	88	107	82	83	98	59	53	96	74	115	90	94	58	64	81	114	85	76	84	51	51	102	91	91	85	76	55	61	83	79	76	83	86	54	55	89	68	94	84	86	52	52	75	80	98	77	77	52	52	93	81	73	65	83	51	52	81	85	89	74	74	48	53	82	68	80	84	73	54	50	67	73	76	72	72	58	50	72	59	80	65	80	42	45	72	82	67	62	87	48	46	74	64	81	82	71	49	49	78	64	59	63	79	49	46	75	80	83	71	90	42	53	70	91	73	80	73	45	56	72	85	78	86	71	55	53	78	70	92	63	67	43	54	91	89	90	90	86	58	51	83	76	70	82	78	61	56	93	99	75	88	85	54	62	94	84	87	91	78	68	56	75	98	82	81	77	58	62	67	79	100	82	99	58	61	94	84	92	108	94	66	59	95	82	97	106	105	73	80	102	101	93	90	114	58	67	103	107	109	117	103	64	65	116	105	107	127	106	51	58	71	105	99	128	99	68	69	112	101	82	118	113	75	78	113	110	87	120	107	67	73	123	118	81	123	111	74	64	126	130	98	106	118	71	75	100	95	120	124	127	69	78	107	114	111	93	131	69	76	120	90	100	131	123	68	77	126	130	121	129
16:00	100	94	67	64	127	114	87	93	118	62	64	106	99	115	95	110	75	62	82	112	88	105	111	66	57	106	118	109	119	107	66	75	100	119	116	114	92	69	74	106	118	83	105	97	70	63	90	92	81	109	100	44	71	100	100	104	96	110	59	71	89	121	84	99	102	59	64	97	84	88	87	101	63	61	73	94	109	103	81	51	54	78	106	65	68	75	58	58	97	86	79	91	79	61	47	78	95	79	62	90	51	50	78	72	77	95	82	60	51	68	70	78	90	71	55	51	74	81	77	72	58	55	49	88	62	56	76	84	48	58	76	81	63	74	76	46	45	61	65	59	62	72	47	47	71	82	58	68	71	39	51	83	65	69	69	80	46	52	69	62	78	66	68	46	58	64	71	66	57	82	45	49	60	61	62	70	70	44	36	64	55	59	60	56	43	49	71	67	59	58	60	54	49	70	53	71	68	67	40	48	73	71	74	69	67	44	43	75	74	61	76	72	43	52	68	61	72	59	71	48	39	65	67	80	68	71	48	49	60	74	61	69	80	44	47	57	76	59	69	72	51	52	68	75	73	72	71	54	49	71	57	79	74	80	60	59	84	81	65	76	91	50	50	78	100	93	94	93	48	64	100	86	92	98	89	54	62	84	81	88	93	107	63	47	87	88	73	99	92	50	55	102	96	80	89	100	58	55	101	101	92	122	83	65	57	92	80	80	86	100	53	60	79	100	92	97	106	60	55	89	118	95	98	99	63	74	90	112	96	94	76	59	68	112	102	96	114	108	63	71	102	120	82	92	87	69	59	87	108	102	86	113	74	70	97	109	99	93	99	63	67	100	93	100	120
17:00	85	73	44	59	64	88	73	76	67	65	48	83	84	80	101	75	52	52	69	89	65	81	88	58	55	62	95	78	71	94	61	49	102	90	92	76	85	52	45	95	81	73	90	95	49	55	89	82	80	82	63	51	45	81	84	81	70	70	59	47	65	75	76	77	71	56	54	77	89	85	69	82	52	52	69	73	81	72	72	44	40	69	76	83	70	66	42	49	60	84	56	69	67	44	44	52	80	69	68	50	42	50	81	66	57	51	73	48	42	61	70	68	69	61	43	37	63	64	64	55	59	40	44	66	62	67	59	67	39	41	64	58	48	67	68	43	39	64	47	52	62	58	40	41	59	46	61	58	59	40	39	58	62	59	52	66	41	40	55	51	45	55	60	37	39	59	56	52	54	55	39	37	50	56	53	53	61	37	40	41	57	51	56	56	46	33	49	49	48	57	52	41	37	61	53	46	58	60	39	38	57	56	62	62	51	34	37	63	58	63	54	54	43	40	65	60	65	59	67	44	40	58	50	59	56	63	41	35	70	65	57	56	60	47	41	51	68	66	61	65	36	37	54	62	56	66	59	46	42	57	66	69	53	69	46	40	71	65	60	60	59	48	38	66	68	57	64	61	40	54	64	58	65	58	83	46	49	78	86	86	82	63	45	47	83	84	68	69	65	50	52	72	63	73	71	96	54	46	71	69	74	78	84	43	54	77	82	66	77	76	53	43	73	78	67	78	68	52	57	68	77	74	89	84	52	46	96	73	70	86	82	57	49	83	89	101	74	77	48	57	72	81	89	77	84	49	56	83	88	71	77	93	52	48	72	83	86	105	75	56	59	82	81	86	79
18:00	55	67	47	45	64	68	52	59	62	45	46	54	65	58	72	55	44	49	65	69	57	62	57	42	38	72	59	58	48	52	43	39	69	68	62	62	64	46	40	52	49	58	62	47	42	38	66	57	58	65	52	40	40	50	59	64	51	42	38	42	65	61	51	55	49	42	43	64	62	59	52	52	37	39	52	64	55	62	58	42	45	60	59	55	53	53	44	35	54	56	63	52	51	42	37	51	47	53	52	60	40	34	49	53	45	54	38	38	37	47	46	56	48	52	38	35	60	44	44	50	49	34	33	44	45	48	49	45	38	32	45	52	46	51	41	34	34	39	42	51	46	40	30	36	49	40	46	48	45	33	34	44	43	45	42	44	34	34	44	44	44	44	45	30	29	45	47	43	43	46	37	33	43	40	36	41	40	37	32	44	46	46	44	45	30	37	48	41	45	42	45	35	32	44	41	46	41	48	30	31	38	41	38	44	47	35	32	43	48	39	44	44	35	33	40	47	41	51	44	35	30	42	47	45	48	50	34	34	48	47	43	46	47	37	35	41	46	46	51	51	38	34	57	53	46	45	44	35	36	47	54	47	48	50	34	36	60	49	58	54	58	36	34	53	44	56	57	52	34	38	53	62	55	50	51	41	35	55	56	65	56	51	44	37	53	48	62	57	52	39	39	53	51	59	65	65	42	52	65	57	64	53	55	36	40	67	56	56	67	52	38	39	67	68	60	48	58	43	41	69	54	62	66	58	39	45	67	61	61	60	53	48	44	59	52	58	62	70	36	36	57	62	62	60	54	48	40	80	60	60	67	64	39	47	54	49	53	70	63	40	45	76	58	58	64
19:00	48	43	35	32	45	52	44	47	43	33	35	42	50	43	43	44	36	37	46	47	44	45	44	34	38	44	45	46	51	40	36	36	47	45	42	46	47	33	34	47	45	52	46	45	32	35	41	46	46	37	41	34	35	44	40	52	47	40	31	31	44	45	40	42	50	36	32	42	39	49	47	46	33	32	41	38	43	44	45	30	33	42	41	42	42	45	29	32	38	35	41	45	39	32	33	36	40	43	40	42	30	30	37	41	39	38	34	30	33	36	40	36	34	37	31	28	36	34	36	37	38	29	28	37	36	36	39	32	31	29	37	36	34	37	35	30	27	36	36	39	37	37	29	29	40	37	38	29	35	29	28	33	30	34	36	33	26	30	34	32	32	37	33	28	27	32	32	38	31	34	28	28	37	31	36	36	39	29	26	31	32	35	34	34	27	27	35	31	32	32	33	26	30	36	35	35	32	36	29	27	34	36	36	36	34	29	26	37	37	36	36	36	28	29	29	34	32	34	37	28	32	35	36	41	35	37	28	28	38	36	37	38	36	28	28	36	35	33	36	35	28	30	37	37	38	41	35	29	31	43	36	40	33	35	28	28	37	44	35	37	40	31	32	36	37	42	39	37	31	30	39	40	41	35	43	30	31	45	36	44	40	40	34	30	41	40	40	38	45	32	31	43	49	43	45	41	33	30	43	46	47	40	39	31	33	41	45	47	43	47	30	33	44	37	49	39	39	34	30	44	44	46	45	45	34	32	51	45	41	44	43	29	30	40	54	47	39	49	33	39	50	38	47	52	51	37	37	50	51	52	50	36	36	34	42	48	54	46	45	32	39	49	49	48	39
20:00	33	36	27	28	35	35	34	33	31	26	29	33	33	40	34	28	28	28	32	32	35	33	36	28	28	31	33	33	33	34	30	26	35	33	33	33	33	28	27	31	33	36	32	30	27	28	33	29	31	38	32	27	26	30	34	32	33	31	28	26	30	33	33	32	35	27	27	33	29	30	34	33	28	26	30	30	30	33	33	28	24	32	32	30	32	34	28	27	31	34	34	30	33	26	25	31	30	31	30	27	27	25	33	31	28	30	28	25	26	31	30	30	30	29	25	25	29	30	29	27	30	26	25	30	31	31	27	31	25	23	29	28	31	29	29	25	23	29	28	30	30	30	25	25	29	27	29	27	28	24	25	27	28	29	31	28	24	24	30	27	29	29	27	23	24	28	29	28	30	27	23	24	27	28	27	26	30	25	24	26	29	27	28	30	24	24	27	26	29	29	28	24	23	28	24	27	29	29	24	25	28	29	28	28	28	24	25	25	29	29	27	29	24	24	26	28	29	27	30	25	25	28	27	29	29	28	25	24	28	29	28	28	29	25	25	29	30	29	28	29	26	26	29	29	29	29	32	25	26	33	30	30	29	29	25	27	28	29	32	30	34	25	26	31	29	30	31	30	25	24	31	28	33	32	33	26	27	32	31	32	30	29	26	27	30	33	31	30	29	27	24	34	32	32	31	32	27	26	31	33	32	31	35	28	27	33	34	31	32	33	28	27	35	34	34	33	29	29	26	34	35	36	33	32	27	29	38	30	33	35	39	28	28	36	33	32	33	34	29	27	34	34	34	34	31	31	28	35	37	32	35	37	28	28	38	36	33	35	32	29	28	34	34	36	31

Usage

use hydroxy_leptos::chart_frame::ChartFrame;
use hydroxy_leptos::heatmap_chart::HeatmapChart;
use leptos::prelude::*;

pub fn demo() -> AnyView {
    let days: Vec<String> = ["Mon", "Tue", "Wed", "Thu", "Fri"].map(String::from).to_vec();
    let hours: Vec<String> = ["9", "10", "11", "12", "13", "14", "15", "16"].map(String::from).to_vec();
    // Sessions per weekday and hour. A NaN is a cell with no data.
    let sessions = vec![
        vec![12.0, 24.0, 31.0, 18.0, 9.0, 22.0, 27.0, 14.0],
        vec![15.0, 29.0, 36.0, 21.0, 11.0, 26.0, 33.0, 17.0],
        vec![14.0, 27.0, 40.0, 25.0, 13.0, 30.0, 35.0, 19.0],
        vec![11.0, 23.0, 33.0, 19.0, f64::NAN, 24.0, 29.0, 13.0],
        vec![8.0, 16.0, 21.0, 12.0, 6.0, 10.0, 12.0, 5.0],
    ];

    // A year of hourly load: 8,760 cells, so the grid draws on a canvas with sparse labels.
    let mut next = noise(11);
    let hours_of_day: Vec<String> = (0..24).map(|h| format!("{h:02}:00")).collect();
    let month_days = [
        ("Jan", 31),
        ("Feb", 28),
        ("Mar", 31),
        ("Apr", 30),
        ("May", 31),
        ("Jun", 30),
        ("Jul", 31),
        ("Aug", 31),
        ("Sep", 30),
        ("Oct", 31),
        ("Nov", 30),
        ("Dec", 31),
    ];
    let dates: Vec<String> = month_days.iter().flat_map(|&(m, n)| (1..=n).map(move |d| format!("{d} {m}"))).collect();
    let load: Vec<Vec<f64>> = (0..24)
        .map(|h| {
            let daily = (-(f64::from(h) - 14.0).powi(2) / 18.0).exp();
            (0..365)
                .map(|d| {
                    let season = 1.0 + 0.3 * (f64::from(d) / 365.0 * std::f64::consts::TAU).cos();
                    let weekend = if (d + 3) % 7 >= 5 { 0.55 } else { 1.0 };
                    (20.0 + 80.0 * daily * season * weekend * (1.0 + 0.15 * normal(&mut next))).round()
                })
                .collect()
        })
        .collect();

    view! {
        <div style="display: grid; gap: var(--space-10);">
        <ChartFrame title="Sessions by weekday and hour" description="Darker cells are busier. Hover a cell, or focus the grid and use the arrow keys.">
            <HeatmapChart
                values=sessions
                rows=days
                columns=hours
                label="Sessions by weekday and hour of day"
                show_values=true
            />
        </ChartFrame>
        <ChartFrame title="Server load through 2026" description="Requests per second, by hour of day. 8,760 cells drawn on a canvas." export=true>
            <HeatmapChart values=load rows=hours_of_day columns=dates label="Requests per second by hour and day" cell_height=10 />
        </ChartFrame>
        </div>
    }
    .into_any()
}

/// A small deterministic random source (xorshift), so server and browser draw the same data.
#[allow(clippy::cast_precision_loss, reason = "a 53-bit fraction is exact")]
fn noise(seed: u64) -> impl FnMut() -> f64 {
    let mut state = seed;
    move || {
        state ^= state << 13;
        state ^= state >> 7;
        state ^= state << 17;
        (state >> 11) as f64 / (1u64 << 53) as f64
    }
}

/// A standard normal sample from two uniform ones (Box-Muller).
fn normal(next: &mut impl FnMut() -> f64) -> f64 {
    (-2.0 * next().max(1e-12).ln()).sqrt() * (std::f64::consts::TAU * next()).cos()
}

use dioxus::prelude::*;
use hydroxy_dioxus::chart_frame::ChartFrame;
use hydroxy_dioxus::heatmap_chart::HeatmapChart;

#[component]
pub fn HeatmapChartDemo() -> Element {
    let days: Vec<String> = ["Mon", "Tue", "Wed", "Thu", "Fri"].map(String::from).to_vec();
    let hours: Vec<String> = ["9", "10", "11", "12", "13", "14", "15", "16"].map(String::from).to_vec();
    let sessions = vec![
        vec![12.0, 24.0, 31.0, 18.0, 9.0, 22.0, 27.0, 14.0],
        vec![15.0, 29.0, 36.0, 21.0, 11.0, 26.0, 33.0, 17.0],
        vec![14.0, 27.0, 40.0, 25.0, 13.0, 30.0, 35.0, 19.0],
        vec![11.0, 23.0, 33.0, 19.0, f64::NAN, 24.0, 29.0, 13.0],
        vec![8.0, 16.0, 21.0, 12.0, 6.0, 10.0, 12.0, 5.0],
    ];

    // A year of hourly load: 8,760 cells, so the grid draws on a canvas with sparse labels.
    let mut next = noise(11);
    let hours_of_day: Vec<String> = (0..24).map(|h| format!("{h:02}:00")).collect();
    let month_days = [
        ("Jan", 31),
        ("Feb", 28),
        ("Mar", 31),
        ("Apr", 30),
        ("May", 31),
        ("Jun", 30),
        ("Jul", 31),
        ("Aug", 31),
        ("Sep", 30),
        ("Oct", 31),
        ("Nov", 30),
        ("Dec", 31),
    ];
    let dates: Vec<String> = month_days.iter().flat_map(|&(m, n)| (1..=n).map(move |d| format!("{d} {m}"))).collect();
    let load: Vec<Vec<f64>> = (0..24)
        .map(|h| {
            let daily = (-(f64::from(h) - 14.0).powi(2) / 18.0).exp();
            (0..365)
                .map(|d| {
                    let season = 1.0 + 0.3 * (f64::from(d) / 365.0 * std::f64::consts::TAU).cos();
                    let weekend = if (d + 3) % 7 >= 5 { 0.55 } else { 1.0 };
                    (20.0 + 80.0 * daily * season * weekend * (1.0 + 0.15 * normal(&mut next))).round()
                })
                .collect()
        })
        .collect();

    rsx! {
        div { style: "display: grid; gap: var(--space-10);",
            ChartFrame {
                title: "Sessions by weekday and hour",
                description: "Darker cells are busier. Hover a cell, or focus the grid and use the arrow keys.",
                HeatmapChart {
                    values: sessions,
                    rows: days,
                    columns: hours,
                    label: "Sessions by weekday and hour of day",
                    show_values: true,
                }
            }
            ChartFrame {
                title: "Server load through 2026",
                description: "Requests per second, by hour of day. 8,760 cells drawn on a canvas.",
                export: true,
                HeatmapChart {
                    values: load,
                    rows: hours_of_day,
                    columns: dates,
                    label: "Requests per second by hour and day",
                    cell_height: 10,
                }
            }
        }
    }
}

/// A small deterministic random source (xorshift), so every platform draws the same data.
#[allow(clippy::cast_precision_loss, reason = "a 53-bit fraction is exact")]
fn noise(seed: u64) -> impl FnMut() -> f64 {
    let mut state = seed;
    move || {
        state ^= state << 13;
        state ^= state >> 7;
        state ^= state << 17;
        (state >> 11) as f64 / (1u64 << 53) as f64
    }
}

/// A standard normal sample from two uniform ones (Box-Muller).
fn normal(next: &mut impl FnMut() -> f64) -> f64 {
    (-2.0 * next().max(1e-12).ln()).sqrt() * (std::f64::consts::TAU * next()).cos()
}

Anatomy

Component	data-part	Renders
`HeatmapChart`	root	figure with a screen-reader table of every cell
	cells	Focusable grid; arrow keys move between cells
	cell	Shaded by --level; dashed when there is no data
	canvas	Draws the cells instead past 2,000 of them, with every twelfth-or-so label
	highlight	Outline on the active cell of a canvas grid
	tooltip	Row, column and value of the active cell
	scale	Lowest and highest value with a colour ramp between
	sr-live	Announces the active cell
	sr-table	Every cell, one row per row label, for screen readers and CSV export

Keyboard

Key	Does
`ArrowLeft / ArrowRight`	Move along the row; the first press lands on the top-left cell
`ArrowUp / ArrowDown`	Move between rows
`Home / End`	First or last cell in the row
`Escape`	Clear the active cell

Props

Prop	Type	Notes
`values`	Vec<Vec<f64>>	Required. One Vec per row. NaN or a short row leaves an empty cell
`rows`	Vec<String>	Required. One label per row
`columns`	Vec<String>	Required. One label per column
`label`	String	Required. What the chart shows; the accessible name
`cell_height`	u16	Cell height in px. Default 36
`show_values`	bool	Print each value in its cell
`format`	Fn(f64) -> String	Formats cells, tooltip, scale and table

Events

Prop	Type	Notes
`on_hover`	Callback<Option<Datum>>	The mark under the pointer or keyboard focus changes, or is left. Fires only on a change
`on_select`	Callback<Datum>	Click, tap or Enter on a mark

Row	9	10	11	12	13	14	15	16
Mon	12	24	31	18	9	22	27	14
Tue	15	29	36	21	11	26	33	17
Wed	14	27	40	25	13	30	35	19
Thu	11	23	33	19	–	24	29	13
Fri	8	16	21	12	6	10	12	5

Row	9	10	11	12	13	14	15	16
Mon	12	24	31	18	9	22	27	14
Tue	15	29	36	21	11	26	33	17
Wed	14	27	40	25	13	30	35	19
Thu	11	23	33	19	–	24	29	13
Fri	8	16	21	12	6	10	12	5

Row	9	10	11	12	13	14	15	16
Mon	12	24	31	18	9	22	27	14
Tue	15	29	36	21	11	26	33	17
Wed	14	27	40	25	13	30	35	19
Thu	11	23	33	19	–	24	29	13
Fri	8	16	21	12	6	10	12	5