Unix Timestamp Converter
Convert a Unix epoch (seconds or milliseconds) to ISO 8601, UTC and local time — or turn any date into a timestamp. Shows the current epoch live and a human-readable relative time.
About this tool
A Unix timestamp is the number of seconds (or milliseconds) since 1 January 1970 UTC, and it shows up everywhere in logs, databases, JWTs, and APIs. This converter turns that raw number into readable ISO 8601, UTC, and local times, and just as easily turns any date back into a timestamp — so you can stop doing epoch math in your head.
It shows the current epoch live so you always have a reference point, and it displays a human-friendly relative time like "3 hours ago" to make the value intuitive. Whether you are debugging an expired token, reading a log line, or setting an expiry, the conversion happens instantly in your browser.
How to use
- Paste a Unix timestamp in seconds or milliseconds to convert it to a date.
- Read the ISO 8601, UTC, and local-time representations of that instant.
- Check the relative time (for example "in 2 days" or "5 minutes ago") for quick intuition.
- To go the other way, enter a date and get its Unix timestamp back.
- Glance at the live current epoch shown on the page whenever you need the value right now.
- Copy whichever representation you need into your code, config, or ticket.
Features
- Two-way conversion — epoch to date and date to epoch — in a single tool.
- Accepts both seconds and milliseconds and detects which you mean.
- Outputs ISO 8601, UTC, and your local time so you can compare zones at a glance.
- Live current epoch counter as a constant reference while you work.
- Human-readable relative time so a raw number becomes instantly meaningful.
- All parsing and formatting run locally in the browser with no server calls.
Frequently asked questions
What is the difference between seconds and milliseconds?
A Unix timestamp in seconds counts whole seconds since 1970, while a millisecond timestamp is one thousand times larger. JavaScript's Date uses milliseconds, whereas many backends and databases use seconds, so check the magnitude — a 13-digit number is usually milliseconds.
Are my timestamps or dates sent to a server?
No. Every conversion is computed in your browser. Nothing you enter is transmitted, so you can safely convert timestamps from private logs or tokens.
Why do I see both UTC and local time?
A timestamp represents a single instant, but it looks different depending on the timezone. Showing UTC and your local time side by side helps you reason about logs from servers that store everything in UTC.
How do I read a JWT exp or iat claim?
Those claims are Unix timestamps in seconds. Paste the number here to see the exact expiry or issue time in a readable format, which is handy when debugging authentication.
What does the relative time mean?
It expresses the distance between the timestamp and now in plain words like "3 hours ago" or "in 5 days", giving you an intuitive sense of the value without doing the math.