Time Calculators

Exact age in years, months, weeks, and days from a date of birth, including age on any date and days to the next birthday.

Find days between dates or add and subtract years, months, weeks, and days, with optional business days and US holidays.

Add or subtract time from a date, find hours between two times, sum HH:MM values, and convert decimal hours.

Find hours between two times or dates, deduct breaks, and convert to decimal hours.

Calculate total work hours and wages from time entries.

Find hours, minutes, and seconds between two times on the same day or across dates, with overnight and decimal-hour results.

See how many weeks and days are left until December 31 from today or any date you choose.

Find the current week of the year in ISO 8601 and US Sunday-start formats.

See today’s date, day of the year, leap-year status, week number, and common date formats.

Learn whether a year has 52 or 53 weeks, including leap years and ISO week rules.

See how many weeks are in each month, plus the average weeks per month for payroll.

Count weeks between two dates, or add and subtract weeks from a starting date.

Count days between two dates, or add and subtract years, months, weeks, and days.

Find the calendar date that falls N weeks from today, with day and week details.

See whether the week starts on Sunday or Monday, and look up the weekday for any date.

Live countdown to a future date and time in days, hours, minutes, and seconds.

Find what time it will be in X hours from now, with a live preset table.

Find what time it was X hours ago, with a live lookback table.

Find the date and weekday X years ago, plus days, weeks, and months back.

Live countdown to a future date and time in days, hours, minutes, and seconds.

Count down from a duration with presets, pause, repeat, and optional chime.

Online stopwatch with start, pause, lap times, and reset.

Set multiple in-browser alarms with presets, sound choices, snooze, and a live clock.

Live clocks for US time zones, DST dates, and which places skip the clock change.

Current time in the United Kingdom (Europe/London), with BST vs GMT and DST dates.