Date & Time
How many working days until the deadline? How many days old is your baby? When to sleep to wake up refreshed? Timestamp conversion, countdowns, age calculation, lunar calendar, world clock, pomodoro — hand the date math over.
Date & Time · 20 tools
Unix Timestamp Converter
Convert Unix epoch timestamps to readable dates and back. Supports second and millisecond precision with multi…
Date Difference Calculator
Compute the interval between two dates in years, months, weeks, days, hours, minutes and seconds. Fully proces…
Date Add / Subtract
Add or subtract days, weeks, months and years from any date to project a target date. Fully processed in your …
Age Calculator
Calculate exact age, Chinese zodiac sign, total days lived and days to your next birthday from your birth date…
Countdown Timer
Create a countdown to any target moment, accurate to the second, with optional alerts.
Stopwatch
Free online stopwatch with millisecond precision and lap splits. Automatically marks your fastest and slowest …
Pomodoro Timer
The classic Pomodoro technique: 25 minutes focused work followed by a 5-minute break to build deep focus habit…
Workday Calculator
Count actual working days between two dates, excluding weekends and optional custom holidays. Fully processed …
World Clock
See the current time, date and weekday in cities worldwide, with timezone search and local time offsets.
Time Unit Converter
Convert between milliseconds, seconds, minutes, hours, days, weeks, months and years with instant results.
Lunar Calendar Converter
Convert Gregorian dates to Chinese lunar dates with zodiac, solar terms and traditional festivals, covering 19…
Flip Clock
A flip clock showing the current time with 12/24-hour formats, optional seconds and fullscreen — great for des…
Multi Timer
Run several independent countdowns at once, each started, paused and reset separately — ideal for cooking, HII…
Sleep Calculator
Find the best time to fall asleep or wake up based on 90-minute sleep cycles. Fully processed in your browser.
Due Date Calculator
Estimate your due date from last menstrual period, IVF transfer or ultrasound data, and track gestational prog…
Baby Days Calculator
Track how many days, weeks and months old your baby is, with growth milestones along the way.
Gaokao Countdown
Live countdown to the Chinese national college entrance exam (Gaokao) in days, hours, minutes and seconds, aut…
Lifespan Calculator
Visualise how much of an expected lifespan you have lived, based on your birth date.
Expiry Date Calculator
Compute expiry dates from production date and shelf life, or work backwards from expiry. Batch support with re…
Chinese Dynasties Timeline
A chronological table of Chinese dynasties from Xia to Qing, with dates, founding emperors and capitals.
Date & time covers timestamps, intervals, countdowns, working days, age, the lunar calendar, world clock, time units, sleep cycles and expiry dates. Results depend on time zones, DST, calendar rules and local conventions.