What this calculator does
A day is defined as exactly 86,400 seconds (24 hours × 60 minutes × 60 seconds), so converting seconds to days is a straightforward division, and converting days to seconds is the same multiplication in reverse. This calculator does either direction and shows the hours and minutes equivalent alongside it.
The main use for this conversion is making sense of a very large second count, such as a script runtime, a server uptime figure, or an age or duration reported in seconds by some system, where 86,400 seconds on its own is not an intuitive quantity until it is restated as 1 day.
The formula
Divide the number of seconds by 86,400 to get days. To convert the other way, multiply the number of days by 86,400 to get seconds. The hours and minutes figures shown alongside use the same seconds total divided by 3,600 and 60 respectively.
| Term | Meaning |
|---|---|
| Second | The base SI unit of time. |
| Day | A period of exactly 86,400 seconds in this conversion (a calendar mean solar day; it ignores the rare leap second some years carry). |
| 86,400 | The fixed number of seconds in a day: 24 × 60 × 60. |
The inputs explained
| Field | What to enter |
|---|---|
| Value | The value to convert: seconds if converting to days, or days if converting to seconds. |
| Convert | Choose which direction you are converting. |
When to use it
Reading a large uptime or duration figure
A server uptime, log duration or script runtime reported in raw seconds is hard to picture; converting it to days makes the scale of the figure obvious immediately.
Working out a target duration in seconds
Some systems, timers and APIs expect a duration in seconds. Converting a plain "30 days" requirement into seconds gives the exact figure to enter.
Sense-checking a large number
A figure such as 86,400 seconds or 2,629,800 seconds means little on its own; restating it in days (1 day, or roughly a month) confirms whether it matches what was expected.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How many days is a given number of seconds?
A range of second counts, from one hour up to roughly a month, converted to days.
| Seconds | Days | In hours |
|---|---|---|
| 3,600 sec | 0.0417 | 1.00 hr |
| 45,000 sec | 0.5208 | 12.50 hr |
| 86,400 sec | 1.000 | 24.00 hr |
| 604,800 sec | 7.000 | 168.00 hr |
| 2,629,800 sec | 30.438 | 730.50 hr |
How many seconds is a given number of days?
A range of day counts, from a single day up to a year, converted to seconds.
| Days | Seconds | In hours |
|---|---|---|
| 1 day | 86,400 | 24.00 hr |
| 7 days | 604,800 | 168.00 hr |
| 30 days | 2,592,000 | 720.00 hr |
| 365 days | 31,536,000 | 8,760.00 hr |
Questions
Why exactly 86,400 seconds in a day?
A day is divided into 24 hours, each hour into 60 minutes, and each minute into 60 seconds: 24 × 60 × 60 = 86,400. This is a fixed, universal conversion factor, not an average or estimate.
Does this account for leap seconds?
No. Leap seconds are occasionally added to civil time to keep it aligned with the Earth's rotation, but they are rare, irregular, and not part of the standard 86,400-second calendar day used for this conversion.
How is this different from the minutes to days calculator?
This page converts directly between seconds and days. The minutes to days calculator does the same thing one step up, using 1,440 minutes per day instead of 86,400 seconds.
What is 86,400 seconds to days?
Exactly 1 day, since 86,400 seconds is the definition of a day used throughout this conversion.
For the same conversion using minutes instead of seconds, see the minutes to days calculator. For seconds expressed as hours and minutes rather than days, see the hours and seconds converter.