Unix Timestamp Converter – Epoch Time to Date Online Free
Unix Timestamp Converter is a free online tool for converting between Unix epoch timestamps and human-readable dates. It displays a live current timestamp, auto-detects seconds vs. milliseconds, supports any IANA timezone, and outputs dates in local time, ISO 8601, and relative format. All processing happens in the browser — no data is sent anywhere.
How to Convert Unix Timestamps Online
- 01
See the live timestamp
The current Unix timestamp is displayed at the top and updates every second. Copy it with one click.
- 02
Convert timestamp ↔ date
Paste a timestamp to see the date in your timezone and ISO 8601 format. Or enter a date to get the Unix timestamp in seconds and milliseconds.
- 03
Copy the result
Click the copy icon next to any output field. Change the timezone selector to instantly re-format the date in any IANA timezone.
Features
- ✓Live current Unix timestamp (updates every second)
- ✓Auto-detect seconds vs. milliseconds
- ✓Timestamp → local time, ISO 8601, relative
- ✓Date string → Unix seconds and milliseconds
- ✓Full IANA timezone support
- ✓100% client-side — native Date API
- ✓One-click copy for all output fields
- ✓No login, no data sent anywhere
Frequently Asked Questions
What is a Unix timestamp?
A Unix timestamp (also called epoch time) is the number of seconds that have elapsed since 00:00:00 UTC on 1 January 1970, not counting leap seconds. It is a standard way to represent points in time in programming because it is timezone-independent and easy to compare arithmetically.
How do I convert a Unix timestamp to a human-readable date?
Paste the timestamp into the "Timestamp → Date" field and click Convert. The tool automatically detects whether the value is in seconds or milliseconds (values greater than 10 billion are treated as milliseconds). The result is shown in your selected timezone, in ISO 8601 format, and as a relative time.
What is the difference between seconds and milliseconds timestamps?
Standard Unix timestamps count seconds since the epoch. JavaScript's Date.now() returns milliseconds (1000× larger). This tool auto-detects the unit: if the number has more than 10 digits it is treated as milliseconds, otherwise as seconds. You can also manually specify milliseconds.
Can I convert dates in different timezones?
Yes. Use the timezone selector to pick any IANA timezone (e.g. America/New_York, Asia/Tokyo). The local time display will reflect the correct offset for that zone. Timestamps themselves are always UTC-based — only the display changes with timezone selection.
What date formats are accepted in the "Date → Timestamp" field?
The field accepts any date string parseable by the JavaScript Date constructor — for example: "2024-06-15", "2024-06-15T12:00:00", "2024-06-15T12:00:00Z", or "June 15, 2024 12:00:00". ISO 8601 format (YYYY-MM-DDTHH:MM:SS) is recommended for unambiguous results.