OmniCalcsDate & Time Calculators
Free date and time tools for age, countdowns, work hours, time zones and timers.
Age Calculator
Your exact age in years, months and days.
Date Difference Calculator
Days, weeks and months between dates.
Countdown Timer
Count down to any event with a progress bar.
Hijri-Gregorian Converter
Two-way Islamic calendar conversion.
Work Hours Calculator
Track hours, breaks and daily pay.
Pomodoro Timer
Focus sessions with break intervals.
Sleep Cycle Calculator
Best bedtimes and wake times in 90-min cycles.
Time Zone Converter
Convert time across 14 world cities.
Stopwatch
Precision stopwatch with lap times.
Day of the Year Calculator
Day number, weeks left and quarter.
Week Number Calculator
ISO week number for any date.
Business Days Calculator
Working days between dates or +N.
Days Until Date
Countdown to any target date in days and weeks.
Weekday Calculator
Day of the week for any date, past or future.
Add Days to Date
Add or subtract days, weeks, months or years.
Time Card Calculator
Weekly hours, overtime and pay.
Time Duration Calculator
Hours, minutes and seconds between two times.
About Date & Time Calculators
Free date and time tools for age, countdowns, work hours, time zones and timers.
Every tool runs entirely in your browser — instant results, no sign-up, no data sent to any server. All formulas are standard and published so you can verify the math yourself.
Frequently Asked Questions
Are these tools really free?
Yes. Every date & time tool on OmniCalcs is 100% free with no registration, and always will be.
Do I need to install anything?
No. All calculators run in your browser with pure HTML, CSS and JavaScript — nothing to download.
How accurate are the results?
Each tool uses standard, published formulas shown on its page, so you can verify every result yourself.