Time Converter

Convert time between milliseconds and years, including weeks, months and more.

How to Use This Converter

Type a value in either box and pick the units. The other box updates instantly. Use the swap button to reverse the direction.

All 9 units are supported in both directions.
Results update live as you type — no button to press.
Values are formatted for readability while staying precise.

Frequently Asked Questions

How many seconds in a day?

86,400 seconds — 24 × 60 × 60.

Why is a month 30.44 days?

The average month over a year (365.25 ÷ 12) is 30.44 days, since months range from 28 to 31 days.

How many hours in a week?

168 hours — 7 days × 24 hours.

What is a "light year"?

A measure of distance, not time — the distance light travels in a year.

Practical Example

Convert 1 week to seconds. One week = 7 days = 168 hours = 10,080 minutes.

168 hours × 60 = 10,080 minutes
10,080 × 60 = 604,800 seconds
604,800 × 1,000 = 604,800,000 milliseconds

What Your Results Mean

Seconds (s) — the SI base unit of time, defined by atomic transitions.
Minutes / Hours / Days — derived units; 1 day = 86,400 seconds.
Months — averaged at about 30.44 days because real months run 28–31 days.
Years / Decades — this converter uses a Julian year of 365.25 days.

Trusted Sources