---
title: "Days to Seconds — d to s converter"
description: "1 day = 86,400 seconds. Convert days to seconds with a full conversion table, the exact formula, and a calculator for any value."
url: https://atoneplace.net/convert/days-to-seconds/
site: "At One Place"
---

# Days to seconds

**1 day in seconds: 1 d = 86,400 s**

s = d × 86,400

To convert days to seconds, multiply by 86,400. The table below gives the values people look up most often, and the converter works for any number.

## Days to seconds table

*Common day values converted to seconds.*

| Days | Seconds |
| --- | --- |
| 1 d | 86,400 |
| 2 d | 172,800 |
| 3 d | 259,200 |
| 4 d | 345,600 |
| 5 d | 432,000 |
| 10 d | 864,000 |
| 15 d | 1,296,000 |
| 20 d | 1,728,000 |
| 25 d | 2,160,000 |
| 30 d | 2,592,000 |
| 40 d | 3,456,000 |
| 50 d | 4,320,000 |
| 75 d | 6,480,000 |
| 100 d | 8,640,000 |
| 250 d | 21,600,000 |
| 500 d | 43,200,000 |
| 1,000 d | 86,400,000 |

## How the conversion works

The relationship is s = d × 86,400. Both units measure time, so the conversion is a fixed factor that never changes.

## Common questions

### How many seconds are in one day?

One day equals 86,400 seconds. s = d × 86,400.

### How do you convert days to seconds?

Use s = d × 86,400. So 10 d is 864,000 s.

### How many days are in one second?

One second equals 0.00001157 days, which is the reverse of the conversion above.

## Related pages

- [Seconds to Days](https://atoneplace.net/convert/seconds-to-days/)
- [Days to Milliseconds](https://atoneplace.net/convert/days-to-milliseconds/)
- [Days to Minutes](https://atoneplace.net/convert/days-to-minutes/)
- [Days to Hours](https://atoneplace.net/convert/days-to-hours/)
- [Days to Weeks](https://atoneplace.net/convert/days-to-weeks/)
- [Days to Months](https://atoneplace.net/convert/days-to-months/)
- [Days to Years](https://atoneplace.net/convert/days-to-years/)

## Sources

- Guide for the Use of the International System of Units (SP 811) — NIST (https://www.nist.gov/pml/special-publication-811) [Public domain (US Government)]
- The International System of Units (SI Brochure) — Bureau International des Poids et Mesures (https://www.bipm.org/en/publications/si-brochure)
- Calculated on this page — At One Place (/about/)