One timestamp,
every form.
Paste a Unix epoch (seconds or milliseconds), an ISO 8601 string, or almost any human-readable date. See every other representation at once. Timezone-aware, DST-correct, copy any format with one click.
Things the tool does — and things it knowingly doesn't.
Seconds vs milliseconds auto-detect
A 10-digit number is parsed as Unix seconds. A 13-digit number is parsed as milliseconds. When the input sits on the boundary (11–12 digits), the tool picks seconds by default and offers a one-click switch.
DST transitions, honestly
Times that don't exist (spring-forward) or happened twice (fall-back) in the selected timezone get a small warning instead of a silent fix. No timestamp tool can be automatically correct at DST boundaries — only transparent.
Day math is DST-aware
Adding 1 day across a DST transition lands on the correct wall-clock time — not 23 or 25 hours later. This matches what users usually want ("same time tomorrow"), not raw 86,400-second addition.
No leap seconds
JavaScript's Date uses POSIX time, which skips leap seconds. This tool uses Date, so it does too. If you're working with precision-timing data that counts leap seconds, this tool is not the right layer.
IANA timezone names
Timezones are listed by IANA name (e.g. America/New_York) because abbreviations like CST are ambiguous — they mean both US Central Standard Time and China Standard Time.
Runs entirely in your browser
Paste timestamps from production logs, API responses, or any other sensitive source. Nothing leaves your device. No server knows what you converted, because there is no server.
Paired with the article ISO 8601 vs Unix epoch vs human-readable — when you need to decide which representation belongs in your schema, not just how to convert between them.