Local-first developer utilities

Time bugs are expensive. Checking them is not.

Parse a production cron expression, inspect an epoch timestamp, or prove how a wall time behaves across DST. Everything runs in this tab.

No account. No pasted data sent away.Your inputs remain in browser memory unless you deliberately copy a share link.

Three focused tools

Start with the value you have.

Each utility states its assumptions, names the time zone in use, and exposes the exact output you need to copy into a test or incident note.

Schedules and timestamps are computed locally. There is no processing API.

UTC, browser-local time, and selected IANA zones are labeled instead of silently mixed.

The cron tool implements five-field Unix semantics. Other scheduler dialects are called out, not guessed.