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Dew point chart

Dew point in °F. Find the air temperature along the top and the relative humidity down the side. Colours are the comfort bands below.
RH	40°	45°	50°	55°	60°	65°	70°	75°	80°	85°	90°	95°	100°	105°
20%	2	6	10	15	19	23	27	31	35	39	44	48	52	56
25%	7	11	16	20	24	28	33	37	41	45	49	54	58	62
30%	11	15	20	24	28	33	37	41	46	50	54	59	63	67
35%	15	19	23	28	32	37	41	45	50	54	59	63	67	72
40%	18	22	27	31	36	40	45	49	54	58	62	67	71	76
45%	20	25	29	34	39	43	48	52	57	61	66	70	75	79
50%	23	27	32	37	41	46	50	55	60	64	69	73	78	83
55%	25	30	34	39	44	48	53	58	62	67	72	76	81	86
60%	27	32	37	41	46	51	55	60	65	70	74	79	84	88
65%	29	34	39	43	48	53	58	62	67	72	77	81	86	91
70%	31	36	41	45	50	55	60	65	69	74	79	84	88	93
75%	33	38	42	47	52	57	62	67	71	76	81	86	91	95
80%	34	39	44	49	54	59	64	68	73	78	83	88	93	98
85%	36	41	46	51	55	60	65	70	75	80	85	90	95	100
90%	37	42	47	52	57	62	67	72	77	82	87	92	97	101
95%	39	44	49	54	59	64	68	73	78	83	88	93	98	103
100%	40	45	50	55	60	65	70	75	80	85	90	95	100	105

Dew point in °C. Find the air temperature along the top and the relative humidity down the side. Colours are the comfort bands below.
RH	5°	7.5°	10°	12.5°	15°	17.5°	20°	22.5°	25°	27.5°	30°	32.5°	35°	37.5°	40°
20%	-16.2	-14.1	-12	-9.9	-7.8	-5.7	-3.7	-1.6	0.5	2.5	4.6	6.6	8.7	10.7	12.8
25%	-13.4	-11.3	-9.2	-7	-4.9	-2.8	-0.6	1.5	3.6	5.7	7.8	9.9	12	14.1	16.2
30%	-11.2	-9	-6.8	-4.6	-2.5	-0.3	1.9	4	6.2	8.4	10.5	12.7	14.8	17	19.1
35%	-9.2	-7	-4.8	-2.6	-0.4	1.9	4.1	6.3	8.5	10.7	12.9	15.1	17.3	19.4	21.6
40%	-7.5	-5.3	-3	-0.8	1.5	3.7	6	8.2	10.5	12.7	14.9	17.2	19.4	21.6	23.8
45%	-6	-3.7	-1.4	0.9	3.2	5.4	7.7	10	12.2	14.5	16.8	19	21.3	23.6	25.8
50%	-4.6	-2.3	0	2.3	4.7	7	9.3	11.6	13.9	16.1	18.4	20.7	23	25.3	27.6
55%	-3.3	-1	1.4	3.7	6	8.4	10.7	13	15.3	17.7	20	22.3	24.6	26.9	29.2
60%	-2.1	0.2	2.6	4.9	7.3	9.6	12	14.3	16.7	19	21.4	23.7	26.1	28.4	30.8
65%	-1	1.3	3.7	6.1	8.5	10.8	13.2	15.6	18	20.3	22.7	25.1	27.4	29.8	32.2
70%	0	2.4	4.8	7.2	9.6	12	14.4	16.8	19.1	21.5	23.9	26.3	28.7	31.1	33.5
75%	0.9	3.4	5.8	8.2	10.6	13	15.4	17.8	20.3	22.7	25.1	27.5	29.9	32.3	34.7
80%	1.8	4.3	6.7	9.1	11.6	14	16.4	18.9	21.3	23.7	26.2	28.6	31	33.5	35.9
85%	2.7	5.1	7.6	10	12.5	14.9	17.4	19.9	22.3	24.7	27.2	29.6	32.1	34.5	37
90%	3.5	6	8.4	10.9	13.4	15.8	18.3	20.8	23.2	25.7	28.2	30.6	33.1	35.6	38
95%	4.3	6.8	9.2	11.7	14.2	16.7	19.2	21.7	24.1	26.6	29.1	31.6	34.1	36.6	39
100%	5	7.5	10	12.5	15	17.5	20	22.5	25	27.5	30	32.5	35	37.5	40

Dry under 50°F
Very comfortable 50–55°F
Comfortable 55–60°F
Getting sticky 60–65°F
Muggy 65–70°F
Oppressive 70–75°F
Miserable 75°F and up

The figures above are the answer for the values this page loaded with. Changing the controls needs JavaScript — without it the calculator cannot recalculate, so read them as one worked example rather than a live result.

What does each dew point mean?

Below 55°F is comfortable and most people never notice it. 60°F is where air starts feeling sticky, 65°F is muggy, 70°F is oppressive, and above 75°F is tropical. The grid above converts any temperature and relative humidity into a dew point; the scale below says what that figure will feel like.

How to read the grid

Air temperature runs along the top, relative humidity down the side, and the cell where they meet is the dew point. That is the whole mechanic. What people get wrong is not the lookup but the interpretation, so the cells are coloured by what the resulting dew point feels like rather than by how large the number is.

Two things the grid assumes: that your humidity figure is for the same air as your temperature figure, and that both are current. A humidity reading from a different hour is a reading of different air.

The scale, band by band

Forecaster convention. The boundary belongs to the band above it, so exactly 60°F is "getting sticky" rather than "comfortable".
Band	Dew point °F	°C	What it feels like
Dry	under 50	under 10	Air this dry takes water readily. Laundry dries, finishes cure, static builds.
Very comfortable	50–55	10–12.8	The range most people never notice at all. Evaporation works without effort.
Comfortable	55–60	12.8–15.6	Pleasant. You would call this a nice day without thinking about the humidity.
Getting sticky	60–65	15.6–18.3	The point at which people start describing the air rather than the temperature.
Muggy	65–70	18.3–21.1	Uncomfortable. Sweat stops evaporating fast enough to keep up with mild exertion.
Oppressive	70–75	21.1–23.9	Heavy air. Overnight lows stay high because the air cannot cool past this.
Miserable	75 and up	23.9 and up	Tropical. Rare outside the deep subtropics, and unmistakable when it happens.

Why the dew point sets the overnight low

A dew point is a floor. Air cannot cool below the temperature at which it saturates without giving up water, and giving up water releases heat, which slows the cooling almost to a stop. So a night with a 70°F dew point will not fall much below 70°F, however clear the sky is.

This is the most practical thing on the page. The forecast low and the dew point are usually within a couple of degrees of each other on a humid night, and if you know one you can predict the other. It is also why humidity climbs after dark without any water being added.

What the colours mean, and what they do not

The bands are about how air feels to a person standing in it. They say nothing about whether something will condense — that depends on the dew point against a surface temperature, which is a different comparison and has its own calculator. A 45°F dew point sits comfortably in the dry band and will still fog a drink taken out of the fridge.

Common questions

Is the dew point comfort scale an official standard?

No, and it is worth being clear about that. It is forecaster convention, published in whole degrees Fahrenheit by National Weather Service offices and widely repeated, but there is no ASHRAE or ISO document behind it in the way there is for the 30–50% relative humidity comfort range. Treat the boundaries as useful round numbers rather than measured thresholds.

Why is the scale in Fahrenheit?

Because that is how it was defined. The bands fall on 50, 55, 60, 65, 70 and 75°F, which are whole numbers in Fahrenheit and awkward ones in Celsius — 10, 12.8, 15.6, 18.3, 21.1 and 23.9. The Celsius view of the chart converts honestly rather than rounding the boundaries to neat metric figures they were never set at.

What is a comfortable dew point?

Anything under about 55°F feels dry and pleasant to most people, and 55–60°F is still comfortable. Discomfort begins in the low 60s and is general by 65°F. There is individual variation and some acclimatisation, so treat these as the middle of a distribution.

How can I print this chart?

Use your browser's print dialog, which can also save it as a PDF. The page has a print stylesheet: the navigation, the calculator controls and the questions are removed, the band colours are forced through, and whichever unit you have selected is the one that prints.

Why does the same relative humidity appear in several bands?

Because relative humidity on its own does not determine the dew point — the temperature does too. 60% at 50°F gives a dew point of 36°F and 60% at 90°F gives 74°F. One is dry air and one is oppressive, and that is precisely the reason the dew point is the more useful figure.

Sources

NOAA / National Weather Service — Dew point vs humidity
ASHRAE Standard 55 — Thermal Environmental Conditions for Human Occupancy — Source of the 30–50% relative humidity comfort range referenced below, not of the dew point scale

Published 31 July 2026