Timestamp Converter

How do I convert Unix timestamps to readable dates?

What this tool does

This converter turns Unix epoch values into the formats developers actually read: ISO 8601, UTC, local time, seconds, milliseconds and a relative label like “3 hours ago.” Paste a number, pick a datetime, or click Now — every field stays in sync so you can copy the format your stack expects.

Why you need it

Logs, databases and APIs rarely agree on how they store time. One service writes seconds since 1970-01-01 UTC; another writes milliseconds; a third returns ISO strings with a Z suffix. When you are debugging an expired token, correlating webhook delivery with a support ticket, or writing a SQL query against a BIGINT column, guessing the format wastes minutes and causes subtle off-by-1000 or off-by-one-hour bugs. A fast, private converter in the browser beats opening three tabs or doing mental math under incident pressure.

How to use it

1. Paste a Unix timestamp in the seconds field, or enter ISO / local text in the other inputs.
2. Click Now to snapshot the current instant across all formats.
3. Compare UTC and Local side by side — they share the same instant but may show different clock faces.
4. Read the Relative row for quick “how long ago” context in logs.
5. Copy seconds, milliseconds, ISO or either timezone string with one click.

Practical examples

• JWT debugging: Decode an exp claim, paste the number here, and confirm whether the token expired in UTC or your local evening.
• Database rows: A PostgreSQL or MySQL epoch column often stores seconds; JavaScript Date.now() returns milliseconds — this tool shows both so you know which to query.
• Log correlation: Match a server line stamped 1710000000 with a client event logged in ISO.
• Scheduling APIs: Convert a meeting time to Unix seconds before sending it to a cron or calendar endpoint.

How it works

Unix time counts non-leap seconds since 1 January 1970 00:00:00 UTC. That anchor is the same everywhere; only the display layer changes. Seconds are the classic ten-digit epoch you see in shell tools and many backends. Milliseconds multiply by 1,000 and appear in JavaScript, some mobile SDKs and several SaaS APIs — paste either and the tool infers the scale from digit length.

UTC is the canonical reference: no daylight saving, no ambiguity. Local applies your operating system timezone rules at that exact instant, including DST offsets. That means the same epoch can map to UTC+1 in winter and UTC+2 in summer without you changing the input. ISO 8601 strings (with or without a Z) round-trip through the datetime picker where supported.

All conversion runs locally in your browser; timestamps are never uploaded.

Common mistakes

• Seconds vs milliseconds: Treating 1710000000 as milliseconds lands you in 1970; treating millis as seconds pushes dates far into the future.
• Assuming “local” is the server zone: Local here means your browser timezone, not necessarily where the log was generated.
• Ignoring DST: A meeting “always at 9:00 local” can be a different UTC offset twice a year — always check UTC for cross-region systems.
• Mixing string formats: 2026-04-15T14:30:00 without a zone is interpreted in local context; add Z or an offset when sharing across teams.

FAQ

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