Unix Timestamp Converter
Convert Unix timestamps to human-readable dates and vice versa. Outputs local time, UTC, ISO 8601, and relative time (e.g., “3 hours ago”).
What Is a Unix Timestamp?
A Unix timestamp represents time as a single integer — the number of seconds elapsed since January 1, 1970, 00:00:00 UTC. This reference point is called the Unix epoch. Unix timestamps are the universal language of time for computers: timezone-agnostic, language-agnostic, and sortable by simple integer comparison.
Where Developers Encounter Timestamps
Database Records
created_at and updated_atfields in PostgreSQL, MySQL, and MongoDB are often stored as Unix timestamps. Paste the value here to verify a record's actual creation time during debugging.
JWT Tokens
JWT tokens use Unix timestamps for exp (expiration), iat (issued at), and nbf (not before) claims. Decode a JWT with our JWT Decoder then convert its timestamps here to check validity.
API Responses and Log Files
Many APIs return timestamps as Unix seconds in JSON responses. Log files often record events as epoch timestamps for efficient parsing and sorting. This converter quickly turns those numbers into readable dates during incident investigation.
Quick Timestamp Reference
| Unix Timestamp | Human-Readable Date (UTC) |
|---|---|
| 0 | Jan 1, 1970 — Unix Epoch |
| 1000000000 | Sep 9, 2001 01:46:40 |
| 1700000000 | Nov 14, 2023 22:13:20 |
| 2147483647 | Jan 19, 2038 — Y2K38 limit (32-bit) |
Frequently Asked Questions
What is a Unix timestamp?
A Unix timestamp (also called epoch time) is the number of seconds that have elapsed since January 1, 1970 at 00:00:00 UTC (the Unix epoch). It is the universal way computers represent time — used in databases, APIs, log files, and JWT tokens.
What is the difference between seconds and milliseconds timestamps?
Most Unix timestamps are in seconds (10 digits, e.g., 1746000000). JavaScript's Date.now() and many APIs return milliseconds (13 digits, e.g., 1746000000000). This converter handles both automatically.
What is the maximum Unix timestamp date?
The maximum 32-bit Unix timestamp is 2,147,483,647 — corresponding to January 19, 2038. This is called the Year 2038 problem (Y2K38). Modern 64-bit systems do not have this limitation.
How do I get the current Unix timestamp in JavaScript?
Use Math.floor(Date.now() / 1000) for seconds, or Date.now() for milliseconds. In Node.js you can also use process.hrtime() for high-resolution timestamps.
Why do JWT tokens use Unix timestamps for exp and iat?
JWT tokens use Unix timestamps because they are language-agnostic and timezone-independent. Any system in any timezone can parse a Unix timestamp to an unambiguous moment in time without locale settings.