Free online time unit converter. Convert seconds to minutes, hours to days, days to weeks, minutes to milliseconds, weeks to months, and more — instant results, strong validation, and a visual comparison chart. Works on phone, tablet and desktop.
Nanoseconds • Seconds • Hours • Days • Years
Years use 365.25 days and months use the average 30.4375 days, so long-range conversions stay accurate rather than drifting.
See the scale difference at a glance — useful when converting between very small (ms) and very large (years) units.
Every conversion runs entirely in your browser — no server, no account, nothing sent anywhere.
Time conversion is one of the most common everyday calculations — figuring out how many minutes are in a workday, how many hours a project will take, how many seconds are in a year, or how many days until a deadline. While the relationships are fixed and simple (60 seconds in a minute, 60 minutes in an hour, 24 hours in a day), the larger units introduce subtleties: a calendar month varies from 28 to 31 days, and a year is not exactly 365 days because of leap years.
The fixed building blocks: 1 minute = 60 seconds. 1 hour = 60 minutes = 3,600 seconds. 1 day = 24 hours = 1,440 minutes = 86,400 seconds. 1 week = 7 days = 168 hours = 604,800 seconds. These never change. The averaged units: because months differ in length, this converter uses the average month of 30.4375 days (365.25 ÷ 12), and a year of 365.25 days to fold in the leap-year correction (one extra day every 4 years). That makes 1 year ≈ 31,557,600 seconds and 1 month ≈ 2,629,800 seconds.
Quick mental shortcuts: There are 86,400 seconds in a day and about 31.5 million seconds in a year (a handy approximation: π × 10⁷ ≈ 31.4 million is famously close). A 90-minute movie is 1.5 hours. A 40-hour work week is 2,400 minutes. There are roughly 8,760 hours in a year (365 × 24), or 8,766 hours using the 365.25-day year.
8-hour shift = 480 minutes = 28,800 seconds. 40-hour week = 2,400 minutes. Full-time year (2,080 hours) = 124,800 minutes. A 25-minute Pomodoro = 1,500 seconds.
1 day = 86,400 s. 1 week = 604,800 s. 1 month ≈ 2.63 million s. 1 year ≈ 31.56 million s. A 2-hour exam = 7,200 s. A 90-day quarter ≈ 2,160 hours.
1 second = 1,000 milliseconds = 1,000,000 microseconds = 1,000,000,000 nanoseconds. A camera shutter at 1/250 s = 4 ms. A 60 fps video frame lasts 16.7 ms.
1 decade = 10 years ≈ 3,652.5 days. 1 year ≈ 52.18 weeks. 1,000,000 seconds ≈ 11.57 days. 1 billion seconds ≈ 31.7 years — a "gigasecond" milestone many people quietly pass in their early 30s.