Timestamp Converter Online
Convert Unix timestamps to human-readable dates and back
Current Unix Time
Pick a date and time to get the Unix timestamp
About this tool
Timestamp Converter Online is a free browser-based tool for converting Unix timestamps to human-readable dates and times, and vice versa. It supports both seconds and milliseconds epoch formats and displays results across 14 major timezones simultaneously — making it ideal for developers debugging API responses, logs, database records, or AI-generated data.
Paste any Unix timestamp and instantly see the equivalent UTC date, ISO 8601 string, relative time (e.g. “3 days ago”), and local times across multiple timezones. You can also go the other direction — pick a date and time to get the corresponding Unix timestamp in seconds and milliseconds.
Everything runs in your browser with no server requests and no data sent anywhere.
Common use cases
- Convert API response timestamps to a readable date for debugging.
- Check what Unix timestamp corresponds to a specific date and time.
- Find the current Unix timestamp in seconds or milliseconds.
- Compare timestamps across timezones when working with distributed teams.
- Convert database createdAt / updatedAt fields from epoch to local time.
- Verify JWT expiry (exp) or issued-at (iat) claim values.
- Convert timestamps in log files to a readable format.
- Calculate relative time — how long ago or until a given timestamp.
- Generate Unix timestamps for test fixtures or seed data.
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, 00:00:00 UTC. It is a common way to represent dates and times in software because it is timezone-independent and easy to compare mathematically.
What is the difference between seconds and milliseconds timestamps?
Unix timestamps in seconds are 10 digits (e.g. 1700000000). Millisecond timestamps are 13 digits (e.g. 1700000000000). JavaScript's Date.now() returns milliseconds, while most server-side languages and APIs return seconds by default.
What is ISO 8601 format?
ISO 8601 is an international standard for representing dates and times, such as 2024-11-14T22:13:20.000Z. The trailing Z means UTC. This format is widely used in JSON APIs, databases, and log files.
Why do some timestamps show as invalid?
Very small numbers (e.g. 0–999) are valid timestamps but represent dates in 1970. Very large numbers may exceed JavaScript's safe date range. Always check whether your timestamp is in seconds or milliseconds — a common source of confusion.
How do I convert a date to a Unix timestamp?
Use the "Date → Timestamp" section: pick a date and time, and the tool immediately shows the corresponding Unix timestamp in both seconds and milliseconds.
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