Unix Timestamp Converter
Convert Unix epoch timestamps to human-readable dates and times, or convert a date back to a Unix timestamp. Supports both seconds and milliseconds. All conversions happen instantly in your browser.
Timestamp → Human Date
Date → Timestamp
What is a Unix Timestamp?
A Unix timestamp (also called epoch time) is the number of seconds that have elapsed since January 1, 1970, 00:00:00 UTC — known as the Unix epoch. It is a simple, timezone-independent way to represent a specific point in time as a single integer. Unix timestamps are used extensively in programming, databases, APIs, log files, and JWT tokens.
Seconds vs Milliseconds
Seconds (10 digits)
Standard Unix timestamp. Example: 1700000000. Used in most Unix/Linux systems, JWT exp and iat claims, and POSIX APIs.
Milliseconds (13 digits)
JavaScript's Date.now() returns milliseconds. Example: 1700000000000. Used in JavaScript, Java, and many modern APIs.
Common Use Cases
- Checking JWT token expiry (
expclaim is a Unix timestamp in seconds) - Reading timestamps from API responses and log files
- Calculating time differences between two events
- Setting expiry times for cookies, sessions, and cache headers
- Debugging date-related bugs in applications
Use the JWT Decoder to inspect exp and iat claims with human-readable dates.