Date & Time Tools

ArrayKit's date and time tools cover the fiddly scheduling and formatting jobs that come up constantly in development and ops. The Unix Timestamp Converter translates epoch seconds or milliseconds into local, UTC and ISO dates and back. The World Clock and Time Zone Converter lines up cities on an aligned 24-hour grid so you can spot overlapping work hours and plan meetings. The Cron Expression Generator builds a crontab schedule field by field, while the Cron Explainer decodes any expression into plain English and previews its next run times. And the UUID Generator produces one or many random v4 identifiers on demand. Built for developers, DevOps engineers and QA testers, every conversion runs entirely in your browser, so timestamps, schedules and IDs are processed locally and never leave your device.

• Unix Timestamp Converter — Convert between Unix timestamps and human dates (local + UTC).
• UUID Generator — Generate one or many random UUID v4 values.
• Cron Explainer — Explain a cron expression and preview its next run times.
• World Clock & Time Zone Converter — Compare times across cities on an aligned 24-hour grid and plan meetings — right in your browser.
• Cron Expression Generator — Visually build a cron expression with live preview, a plain-English summary and next run times.
• Date Duration Calculator — Calculate the duration between two dates in years, months, weeks, days and business days.
• Age Calculator — Calculate exact age in years, months and days as of any date, plus totals in weeks, days, hours and next birthday.
• Duration Converter — Convert a duration between seconds, minutes, hours, days, HH:MM:SS and human formats.
• Business Days Calculator — Add or subtract working days from a date, or count business days between two dates.
• Date Calculator — Add or subtract years, months, weeks and days from a date to find the resulting date.
• Time Duration Calculator — Calculate the hours and minutes between two times of day, even across midnight.
• ISO Week Number Calculator — Find the ISO-8601 week number for any date, and the date range for a given week.
• strftime Date Formatter — Format a date with strftime tokens (%Y, %m, %d…) and preview the output live.
• Relative Time Formatter — Turn a date into a human "time ago" phrase, or humanize a duration.
• Time Calculator — Add or subtract times and durations, and sum multiple time spans.
• Time Card Calculator — Total daily and weekly work hours from clock-in/out times minus breaks.
• Day of the Week Calculator — Find the day of the week for any date, past or future.
• Sunrise & Sunset Calculator — Sunrise, sunset, solar noon, twilight and golden hour for any date and location.
• Moon Phase Calculator — Moon phase, illumination and age for any date, with a full-month phase calendar.

Frequently asked questions

What can I do with ArrayKit's date and time tools?

You can convert Unix timestamps to and from local, UTC and ISO dates, compare times across cities on a world clock and plan meetings, build a cron expression visually or decode an existing one and preview its next runs, and generate random UUID v4 identifiers. Together they cover the most common date, time, and scheduling tasks developers face.

Which cron tool should I use — the Generator or the Explainer?

Use the Cron Expression Generator to build a new crontab schedule by picking each field, with a live plain-English summary and next run times. Use the Cron Explainer when you already have an expression and want to decode what it means and confirm when it will fire next.

Can these tools handle time zones and daylight saving time?

Yes. The World Clock & Time Zone Converter aligns cities on a shared 24-hour grid and applies daylight saving rules automatically using your browser's built-in time-zone database, and the timestamp and cron tools render results in your device's local time zone.

Are the date and time tools safe to use with sensitive data?

Yes. Every tool runs entirely in your browser, so your timestamps, schedules, cron expressions and identifiers are processed locally and never leave your device. Nothing you enter is uploaded to a server.

Do the date and time tools work offline?

Yes. Because all processing happens locally in your browser, the timestamp converter, world clock, cron tools and UUID generator keep working even without an internet connection once the page has loaded.

Who are these date and time tools built for?

They are built for developers, DevOps and site-reliability engineers, QA testers, data engineers and anyone debugging logs, APIs, databases or schedulers, where epoch timestamps, cron jobs, time-zone math and unique IDs come up every day.