Time Tools

Convert a 12-hour AM/PM time like 2:30 PM into 24-hour format like 14:30.

Convert a 24-hour clock time like 14:30 into 12-hour AM/PM format like 2:30 PM.

Find the age gap between two people in years, months, and days from their birth dates.

Draw a live-updating or custom-time analog clock face as a downloadable SVG or PNG.

Average a list of calendar dates and get the mean date back.

Average a list of clock times correctly, using a circular mean instead of plain arithmetic.

Get a full breakdown of a calendar date: weekday, day of year, week of year, quarter, and more.

Subtract a number of days, weeks, months, or years from a calendar date.

Reformat a YYYY-MM-DD date into any custom layout using format tokens.

Turn a precise calendar date into an imprecise description, like "early August 2026".

Turn a calendar date into a natural spelled-out phrase, like "the fifth of August, twenty twenty-six".

Add a number of days, weeks, months, or years to a calendar date.

Round a calendar date to the nearest week start, month start, or year start.

Sort a list of YYYY-MM-DD calendar dates into chronological order.

Round a calendar date down to the start of its month or the start of its year.

Check whether a YYYY-MM-DD date actually exists, with correct leap-year handling.

Convert a cat's age in years into its approximate equivalent in human years.

Find which day of the week December 25 falls on for a single year or a range of years.

Calculate the exact angle of the hour, minute, and second hands for any time.

Find the clock time that matches a given hour hand and minute hand angle.

Break down a clock time into AM/PM, elapsed seconds, clock hand angles, and a palindrome check.

Subtract a duration like "2h45m" from a clock time, wrapping back past midnight into the previous day.

Format a 24-hour clock time into a custom pattern using HH, hh, mm, ss, and A tokens.

Turn a precise clock time into an imprecise spoken description, like "just after half past three".

Turn a 24-hour clock time into a natural spoken phrase, like "quarter past three in the afternoon".

Add a duration like "2h45m" to a clock time, wrapping past midnight into the next day.

Round a 24-hour clock time to the nearest multiple of a chosen interval, from 1 to 1440 minutes.

Sort a list of clock times into chronological order within a single day.

Truncate a 24-hour clock time down to the hour or the minute, discarding the finer components.

Check whether a clock time is valid and see its 12-hour or 24-hour equivalent.

Check whether a single year is a common (non-leap) year, with the rule that applied.

List every common (non-leap) year within a given year range.

Generate a sequence of calendar dates from a start date, a step like "10 days" or "1 month", and a count.

Generate a sequence of clock times from a start time, a step like "90m" or "2h", and a count, wrapping past midnight.

Turn a year and an ordinal day number back into the calendar date it represents.

Find the number of days between two dates, plus a years/months/days breakdown.

Sort a list of start-to-end date ranges by their start date.

Split a date range into a chosen number of equal sub-ranges.

Turn a list of labeled date ranges into a Gantt-style horizontal bar-chart timeline.

Generate a list of dates starting from a given date, stepping by a fixed number of days.

Convert a Gregorian calendar date into its Julian Day Number.

Find the weekday name for any calendar date.

Find which ordinal day of the year a calendar date falls on, from 1 to 366.

Convert a number of days, including decimals, into the equivalent number of hours.

Render a live-updating digital clock in the browser, switchable between 24-hour and 12-hour display.

Convert a dog's age in years into its approximate human-year equivalent.

Find the date of Western (Gregorian) Easter Sunday for a year or range of years.

List every Friday the 13th within a given year or year range.

Convert a modern Gregorian calendar date into its Julian calendar equivalent.

Convert a number of hours into whole days plus the leftover remainder hours.

Convert a human age into where it lands on the classic cat-aging chart, expressed in actual cat years.

Convert a human age into the equivalent dog age using a tiered aging curve.

Convert a readable UTC date and time into a UNIX timestamp in seconds.

Convert a Julian Day Number into its Gregorian calendar date.

Convert an old-style Julian calendar date into its modern Gregorian calendar equivalent.

List which day of the week July 4th falls on for every year in a given range.

Check whether a single year is a leap year, with the rule that applied.

List every leap year within a given year range.

List every date in a year range whose 8 digits (MMDDYYYY) are strictly increasing, strictly decreasing, or all identical.

List every clock time in an hour range whose 4 digits (HHMM) are strictly increasing, strictly decreasing, or all identical.

Visualize a lifespan as a grid of weeks lived and weeks remaining, from a birth date and life expectancy.

Convert military time like 1430 or "1430 hours" into regular 12-hour clock time.

Find what a digital or analog clock's time looks like when reflected in a mirror.

Draw a full monthly calendar grid for any year and month, with today highlighted and month-to-month navigation.

Find what day of the week New Year's Day (January 1st) falls on, for a single year or a range of years.

List every date in a year range whose 8 digits (MMDDYYYY) read the same forwards and backwards.

List every clock time in an hour range whose 4 digits (HHMM) read the same forwards and backwards.

Generate a batch of random calendar dates within a chosen year range, using cryptographically secure randomness.

Generate a batch of random clock times, using cryptographically secure randomness.

Generate cryptographically random UNIX timestamps within an optional min/max range.

Convert 12-hour AM/PM times into 4-digit military time format.

Enter a date and hemisphere to get its meteorological season.

Find how many seconds have elapsed since 00:00:00 for a given clock time.

Find how many seconds remain until the next 00:00:00 for a given clock time.

Convert a whole number of seconds into HH:MM:SS format, with hours allowed to exceed 24.

Find the exact date of an ordinal weekday, like "the 2nd Tuesday of March" or "the last Friday of June".

Find the exact date of US Thanksgiving, the fourth Thursday of November, for a single year or a range of years.

Find the duration between two clock times, wrapping to the next day if needed.

Sort a list of start-end time ranges by their start time.

Split a total duration into a chosen number of equal-length time intervals, with exact boundary times for each.

Turn a list of labeled same-day time intervals into a horizontal bar-chart timeline.

Generate a list of clock times starting at a given time, spaced by a fixed step.

Convert a duration written as HH:MM:SS or HH:MM into its total number of seconds.

Convert a local date and time from one IANA time zone to its equivalent wall-clock time in another.

Generate a list of evenly spaced UNIX timestamps from a start, step, and count.

Convert a UNIX timestamp in seconds into a readable UTC calendar date and time.

Find a date's ISO 8601 week number, with weeks starting Monday and week 1 anchored to the year's first Thursday.

See the current time in a list of IANA time zones side by side, refreshed on demand.

Print the full Western zodiac calendar, all 12 signs and their date ranges at a glance.

Enter a birth date and get its Western (tropical) zodiac sign.