A growing set of free, accurate calculators for working with dates and time. Every tool runs instantly in your browser with no sign up.
Calculate your exact age, age gaps, biological body age, specific date age, and total lifespan in smaller time units.
Calculate your birthday count downs, retirement projections, what generation you belong to, half birthdays, and rare anniversaries.
Convert dog and cat years into human equivalent ages based on breed size, weight, and veterinary growth charts.
Measure elapsed time since major historical events, or look up registration age metrics for any website domain.
Compute your exact orbital age, birthday intervals, and planetary years across the solar system.
Find dates, measure the time between dates, and move forward or backward across the calendar.
Measure elapsed time between two points, count working days, and plan around business calendars.
Move backward or forward from today, or count down to a future date and time.
Convert between Unix timestamps, spreadsheet serial numbers, Discord codes, and human dates.
Convert between time units and switch between 12 hour, 24 hour, and different date formats.
Add, subtract, multiply, divide, and average lengths of time, and work with time percentages.
Plan sleep, study, reading, screen time, and travel around the hours in your day.
These calculators help you answer everyday questions about dates and time. You can add or subtract time from a date, measure the gap between two dates, find the day number or week number of any date, and see which quarter a date falls in.
Every tool is free to use, works on phones and computers, and gives an instant answer the moment you change an input. More calculators for durations, timestamps, and planning are on the way.