Day to Second
Convert Day to Second instantly. Free online astronomy unit converter with exact formula, conversion table and FAQ.
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Formula
second = day × 86400
day = second × 1.15740741e-5
Conversion table
| 1 d | 86400 s |
| 5 d | 432000 s |
| 10 d | 864000 s |
| 20 d | 1.728e+6 s |
| 50 d | 4.32e+6 s |
| 100 d | 8.64e+6 s |
| 500 d | 4.32e+7 s |
| 1,000 d | 8.64e+7 s |
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Frequently asked questions
What is the source unit in this conversion?
The source unit is the day (d). A day is 86,400 seconds, the time for Earth to complete one rotation relative to the Sun.
What is the destination unit in this conversion?
The destination unit is the second (s). The second is the SI base unit of time.
How do I convert day to second?
Multiply the day value by 86400. For example, 10 d × 86400 = 864000 s.
Is the day to second conversion exact?
Yes. Both units have a fixed, defined relationship to the astronomy converter's time base unit, so the conversion factor is exact rather than a measured approximation.
Where is this conversion commonly used?
It's used in astronomy, physics, and space science whenever a time value expressed in day needs to be compared with, or reported in, second.
Can I convert second back to day?
Yes. Multiply the second value by 1.15740741e-5 to get day.
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About this conversion
This page converts day (d) to second (s) within the astronomy converter.
A day is 86,400 seconds, the time for Earth to complete one rotation relative to the Sun.
The second is the SI base unit of time.
The formula is second = day × 86400, based on each unit's fixed relationship to the astronomy converter's time base unit.
The conversion is exact, since it relies on a fixed numerical ratio between the two units rather than a measured or approximate value.
Use the calculator above for instant results, or the table below for common day values already converted to second.