Your files stay on your device

Time tools

Timestamps, time zones and durations, computed entirely in your browser.

- Timestamp converter

Unix to ISO 8601 and back, with relative time.
 (/time/timestamp-converter)
- Timezone converter

One moment across every zone, laid out side by side.
 (/time/timezone-converter)
- Duration converter

Milliseconds up to weeks, with a human breakdown.
 (/time/duration-converter)
- Availability sharer

Share free slots by link. No calendar connection.
 (/time/availability)
- Date math

Add durations to a date and diff two dates, wall-clock vs elapsed across DST, both stated.
 (/time/date-math)
- Calendar converter

Gregorian ⇄ Hijri, Hebrew, Persian, Chinese, and eleven more, from your browser's ICU tables.
 (/time/calendar-converter)
- ISO 8601 Duration

Parse and build ISO 8601 durations: exact elapsed totals for time units, honest refusal to invent one for months.
 (/time/iso-duration)
- ISO Week Number

Date to ISO week date and back: week 1 holds the first Thursday, weeks start Monday.
 (/time/week-number)
- Business Day Calculator

Count or add business days with your own holiday list and weekend definition. No holiday API exists here.
 (/time/business-days)
- Stopwatch and Countdown

A stopwatch with laps and a countdown: wall-clock math that survives background throttling, memory-only.
 (/time/stopwatch)
- Epoch Batch Converter

Many Unix timestamps at once (ISO, UTC, RFC 2822, relative), with row and byte caps.
 (/time/epoch-batch)

11 tools · your files are processed on your device. The few tools that talk to the internet say so before they do.

Canonical HTML: https://nutter.tools/time
Markdown version: https://nutter.tools/time/index.md
Plain-text version: https://nutter.tools/time/index.txt
Agent index: https://nutter.tools/llms.txt