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Date & Time Tools

30 tools

Convert Unix epoch timestamps to human-readable ISO 8601 dates and timezones.

All Date & Time Tools Time Converters (9) Timers & Stopwatches (4) Date Calculations (17)
Time Converters Processed in your browser
Unix Timestamp Converter
Convert Unix seconds and milliseconds to UTC, ISO 8601, and local time zones, or convert dates back to epoch timestamps.
Date Calculations Processed in your browser
Date Difference & Business Days Calculator
Calculate exact days between two dates, working business days, weeks, months, or add and subtract days to find future dates.
Timers & Stopwatches Processed in your browser
Pomodoro Focus Timer
Clean, customizable Pomodoro focus timer with audio chimes, SVG progress ring, break cycles, and browser notifications.
Date Calculations Processed in your browser
Flight Duration & Jet Lag Direction Calculator
Calculate flight duration across departure/arrival timezones and estimate jetlag recovery days.
Date Calculations Processed in your browser
Moon Phase & Lunar Calendar Calculator
Calculate current moon phase, illumination percentage, and lunar age with visual moon graphic.
Date Calculations Processed in your browser
Sunrise, Sunset & Solar Noon Astronomical Calculator
Calculate precise astronomical sunrise, sunset, solar noon, dawn, and dusk for any global coordinates.
Date Calculations Processed in your browser
Multi-City Timezone Meeting Overlap Scheduler
Find optimal working hour meeting overlaps across multiple global timezones (NYC, London, Tokyo).
Time Converters Processed in your browser
Astronomical Julian Day & MJD Converter
Convert calendar Gregorian dates into astronomical Julian Day Number (JDN) and Modified Julian Day (MJD).
Timers & Stopwatches Processed in your browser
Online Stopwatch & Lap Timer
High-precision digital stopwatch with lap and split times, fastest/slowest lap tracking, and CSV export.
Date Calculations Processed in your browser
Golden Hour & Blue Hour Photography Calculator
Calculate photography Golden Hour, Blue Hour, and solar twilight times (Civil, Nautical, Astronomical) for any date and coordinates.
Date Calculations Processed in your browser
Planetary Age & Astronomical Calendar Calculator
Calculate your exact astronomical age in years and days across all planets in our solar system with next planetary birthday countdowns.
Time Converters Processed in your browser
Islamic Hijri and Gregorian Calendar Date Converter
Convert dates between the Islamic Hijri lunar calendar (Umm al-Qura) and the Gregorian calendar with Ramadan and Eid markers.
Date Calculations Processed in your browser
Timestamp Difference & Duration Calculator
Calculate the exact elapsed time and duration between two Unix timestamps or calendar dates in years, days, hours, and business days.
Date Calculations Processed in your browser
Gregorian Leap Year & Century Math Verifier
Evaluate leap year status, 400-year cycle exceptions, and tropical year drift using precise astronomical algorithms.
Date Calculations Processed in your browser
Global Multi-City Meeting Time Overlap Matrix
Visualize green business hour overlap windows across multiple worldwide time zones simultaneously.
Date Calculations Processed in your browser
Corporate Fiscal Year & 4-4-5 Retail Period Calculator
Compute corporate quarterly fiscal boundaries, 4-4-5/4-5-4 retail accounting periods, and fiscal week numbers.
Date Calculations Processed in your browser
Solar Noon, Twilight & Daylight Length Calculator
Compute exact solar noon, civil twilight, and daylight hours for any latitude and day of the year.
Date Calculations Processed in your browser
24/7 Work Shift Rotational Schedule Planner
Model industrial and healthcare rotational shift patterns (4-on-4-off, Panama, DuPont) across teams with calendar visualization.
Time Converters Processed in your browser
Hebrew (Jewish) Lunar-Solar & Gregorian Calendar Converter
Convert dates bi-directionally between the Hebrew lunisolar calendar and civil Gregorian dates with Jewish year computation.
Time Converters Processed in your browser
Cron Expression Next Execution Runs Visualizer
Parse 5-part crontab expressions and display the next 10 exact execution timestamps with human-readable explanations.
Time Converters Processed in your browser
Precision Time Unit & Epoch Resolution Converter
High-precision conversion between nanoseconds, microseconds, milliseconds, seconds, hours, solar days, and Julian years.
Timers & Stopwatches Processed in your browser
Live Event Date & Target Time Countdown Ticker
Track exact remaining days, hours, minutes, and seconds until upcoming milestones, product launches, or holidays with live audio chime.
Timers & Stopwatches Processed in your browser
Circadian Power Nap & Focus Recovery Timer
Scientific nap timer with preset windows for 10-minute alertness, 20-minute motor memory, and 90-minute REM rejuvenation.
Date Calculations Processed in your browser
Detailed Age & Milestone Calculator
Calculate your exact age in years, months, weeks, days, hours, minutes, and seconds with next birthday countdown.
Date Calculations Processed in your browser
Business Days & Working Days Calculator
Calculate the number of business days between two dates, or add/subtract working days excluding weekends.
Date Calculations Processed in your browser
Day of the Year & Leap Year Progress
Discover the exact day number of the year (1-366), days remaining, leap year status, and live annual completion percentage.
Date Calculations Processed in your browser
Time Duration & Timesheet Calculator
Calculate hours and minutes between two times with lunch break deductions and total pay calculation.
Time Converters Processed in your browser
ISO 8601 & RFC Timestamp Formatter
Parse, convert, and format dates into ISO 8601, RFC 2822, RFC 3339, Unix Epoch, and UTC strings.
Time Converters Processed in your browser
Time Ago & Relative Date Calculator
Calculate human-friendly relative time phrases (e.g. 3 hours ago, in 5 days, 2 months ago) and reciprocal calendar dates.
Time Converters Processed in your browser
World Time Zone Converter & Meeting Planner
Compare multiple global time zones simultaneously with an interactive 24-hour meeting time planner slider.

🛡️ Exécution côté client & Architecture de confidentialité

Chaque outil s'exécute selon une architecture stricte de confidentialité locale (P0) sans envoi vers des serveurs distants.

🔒 Zéro enregistrement de données
No tracking or database recording of your inputs, keys, or source documents.
⚡ Traitement local instantané
Zero network latency or server queue delays. Output is rendered instantaneously.
🌐 Fonctionne hors ligne
Continue working even during intermittent internet or offline environments.

Frequently Asked Questions

Are all Date & Time Tools tools free?

Yes, 100% free with unlimited daily usage. There are no paywalls, subscriptions, or login requirements.

Is my data uploaded or stored anywhere?

Never. All operations happen in-memory inside your browser session. Once you refresh or close your browser tab, memory is cleared immediately.

Can I use these utilities on mobile or tablet?

Yes, all utilities are fully responsive and optimized for touch devices and small viewports without loss of functionality.

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