Free Time & Date Tools Online
Tools for working with time: convert Unix timestamps, translate between time zones, and calculate the exact difference between two dates.
17 free tools · No signup · Runs in your browser
All Time & Date tools
Unix Timestamp Converter
Convert between Unix timestamps and human-readable dates.
Timezone Converter
Convert a time between any two time zones.
Date Difference Calculator
Calculate days, weeks, months and years between two dates.
Countdown Timer
Live countdown to any future date and time, ticking second by second.
World Clock
Live clocks across multiple timezones with offsets and dates.
Workday Calculator
Add or subtract business days, optionally skipping weekends and US federal holidays.
Week Number Calculator
ISO 8601 and US week numbers, day of year and days remaining.
Weekday Finder
Look up the day of the week for any date, in multiple languages.
Leap Year Checker
Tells you if a year is a leap year and lists the next 5 leap years.
Cron Expression Parser
Describe any 5-field cron expression and preview the next 10 fire times.
Meeting Planner Across Timezones
Find overlapping work hours for participants in different timezones.
Date Formatter
Format any date with day.js-style tokens like YYYY-MM-DD HH:mm:ss.
Roman Numeral Date Converter
Convert dates to Roman numerals (e.g. VIII·V·MMXXVI) and back.
Add or Subtract Days
Add or subtract days, weeks, months or years from any date.
Quarter Calculator
Find the fiscal or calendar quarter for any date, with start, end and progress.
ISO Week Calculator
Convert ISO year + week to start (Monday) and end (Sunday) dates.
Duration Calculator
Add up multiple HH:MM:SS durations and see the total, average and breakdown.
About our time & date tools
Working with time is famously the source of most production bugs — daylight saving transitions, leap years, timestamps in seconds vs milliseconds, and the seventy-something IANA timezones. BestMint's time and date tools take the guesswork out of the three most common operations: converting Unix timestamps to readable dates and back, translating between time zones, and computing exact differences between two dates.
The Unix Timestamp Converter auto-detects whether your input is in seconds (10 digits, the Unix standard) or milliseconds (13 digits, JavaScript's Date.now), and displays the result in both UTC and your local time. A one-click 'now' button gives you the current epoch instantly — handy for log inspection, cache busting and JWT exp claims.
The Timezone Converter pulls from the IANA timezone database via the browser's Intl API, which means daylight saving transitions are handled correctly (including historical and upcoming changes). Pick a source zone, target zone(s) and a date/time and you'll see the equivalent local time everywhere. The Date Difference Calculator returns the exact span between two dates in days, weeks, months and years — with an optional business-day mode that excludes weekends, useful for project planning and SLA calculations.
What’s included in this category
- Unix Timestamp Converter — Convert between Unix timestamps and human-readable dates.
- Timezone Converter — Convert a time between any two time zones.
- Date Difference Calculator — Calculate days, weeks, months and years between two dates.
- Countdown Timer — Live countdown to any future date and time, ticking second by second.
- World Clock — Live clocks across multiple timezones with offsets and dates.
- Workday Calculator — Add or subtract business days, optionally skipping weekends and US federal holidays.
- Week Number Calculator — ISO 8601 and US week numbers, day of year and days remaining.
- Weekday Finder — Look up the day of the week for any date, in multiple languages.
- Leap Year Checker — Tells you if a year is a leap year and lists the next 5 leap years.
- Cron Expression Parser — Describe any 5-field cron expression and preview the next 10 fire times.
- Meeting Planner Across Timezones — Find overlapping work hours for participants in different timezones.
- Date Formatter — Format any date with day.js-style tokens like YYYY-MM-DD HH:mm:ss.
- Roman Numeral Date Converter — Convert dates to Roman numerals (e.g. VIII·V·MMXXVI) and back.
- Add or Subtract Days — Add or subtract days, weeks, months or years from any date.
- Quarter Calculator — Find the fiscal or calendar quarter for any date, with start, end and progress.
- ISO Week Calculator — Convert ISO year + week to start (Monday) and end (Sunday) dates.
- Duration Calculator — Add up multiple HH:MM:SS durations and see the total, average and breakdown.