Days to Hours Converter (d to h)

Convert days to hours instantly. 1 d = 24 h. Includes the formula, a full conversion table and a calculator that works offline.

The formula

To convert days to hours, multiply by 24:

h = d × 24

Going the other way, divide instead — or multiply by 0.0417, which is the same thing:

d = h × 0.0417

Days to Hours conversion table

Days	Hours
1 d	24 h
2 d	48 h
3 d	72 h
4 d	96 h
5 d	120 h
6 d	144 h
7 d	168 h
8 d	192 h
9 d	216 h
10 d	240 h
15 d	360 h
20 d	480 h
25 d	600 h
30 d	720 h
40 d	960 h
50 d	1,200 h
75 d	1,800 h
100 d	2,400 h
250 d	6,000 h
500 d	12,000 h
1000 d	24,000 h

Hours to Days

Hours	Days
1 h	0.0417 d
2 h	0.0833 d
3 h	0.125 d
4 h	0.1667 d
5 h	0.2083 d
6 h	0.25 d
7 h	0.2917 d
8 h	0.3333 d
9 h	0.375 d
10 h	0.4167 d

What that actually looks like

A conversion factor is hard to judge on its own. These are quantities most people already have a feel for, converted for you:

A working week is 5 days — 120 h
A month is about 30 days — 720 h

Why both units are still in use

Time conversions look trivial until months and years get involved. A month is not a fixed length, and a year is 365 days except when it is 366. This page uses 365-day years and 30-day months, which is the convention for rough planning; for contracts, interest or anything legal, count the actual calendar days.

Mistakes worth avoiding

Working days are not calendar days. A 30-day payment term is calendar days unless the contract says otherwise, which is roughly 21 working days — a gap large enough to miss a deadline over.

The other habit worth breaking is rounding too early. Convert first, round once at the end, and you avoid the drift that turns a small approximation into a visible error by the third calculation.

Doing it in your head

When you only need a rough answer, there is nothing to approximate — the factor is the whole number 24, so multiply and you have the exact answer. Ten days is 240 hours. An estimate is enough for deciding whether something will fit or whether a figure sounds plausible. When the number has to be right — because you are buying, cooking or building to it — use the calculator and let it carry the decimals.

Common questions

How many hours are in one day?

One day equals 24 hours. The calculator above handles any value, including decimals and very large numbers, and updates as you type.

Is this an exact conversion?

Yes — this is an exact defined ratio, not an approximation. The table rounds for readability; the calculator does not.

Does this work offline?

Yes. The conversion runs in your browser with no network request, so it works on a plane, in a basement, or on a phone with no signal once the page has loaded.