Milliseconds to Seconds Converter

One second is 1,000 milliseconds. Programming timeouts, audio delays and reaction tests use milliseconds.

How to use the Milliseconds to Seconds Converter

1. Type the number of milliseconds into the Milliseconds field. Decimals such as 750 are fine.
2. Read the answer in Seconds – it updates as you type, with no button to press.
3. To convert the other way, type into Seconds and the milliseconds are recalculated.
4. Press Copy results to copy both values with the page title, or Copy link to share this exact conversion.

This page converts only ms ⇄ s. Need a different unit? Use the general time converter, where you can choose any “from” and “to” unit.

How it works

Both units measure time, so they are always in the same ratio: one millisecond equals 0.001 seconds. The calculator multiplies the number of milliseconds you type by 0.001 to give seconds, and when you type into the seconds field it divides by the same factor to give milliseconds. Because the ratio never changes, doubling the milliseconds always doubles the seconds. Results are calculated at full precision and rounded only for display (up to eight decimal places, with very large or small values shown in scientific notation).

How to convert milliseconds to seconds

1. Write down the value in milliseconds, for example 1,500 ms.
2. Multiply by the conversion factor 0.001 (because 1 millisecond = 0.001 s).
3. 1,500 × 0.001 = 1.5 s.
4. To go back from seconds to milliseconds, divide by 0.001 – or multiply by 1,000.

ms to s conversion table

What is a millisecond?

A millisecond is one thousandth of a second. Network latency, reaction times and computer timers are measured in milliseconds.

What is a second?

The second is the SI base unit of time, defined by 9,192,631,770 cycles of radiation from a caesium-133 atom.

Common mistakes to avoid

Treating every month as 30 days or every year as 365 days in long calculations, and writing decimal hours such as 1.5 h as 1 h 50 min (it is 1 h 30 min).