Convert Unix timestamps to human-readable dates, and back.
About this tool
Enter a Unix timestamp (seconds or milliseconds — auto-detected by digit length) or a date string to see it converted to ISO 8601, UTC, your local time zone, a relative time ("3 hours ago"), and both Unix seconds and milliseconds. All conversion uses your browser's built-in Date object.
Enter a Unix timestamp or a date string and Tabreon instantly shows ISO 8601, UTC, local time, relative time, and both seconds- and milliseconds-based Unix formats.
Why use Tabreon for this?
Conversion runs client-side using your browser's own Date object — nothing is sent to a server.
Automatically detects whether a numeric input is Unix seconds or milliseconds, based on digit length.
Also accepts a plain date string as input, not just a numeric timestamp.
How to convert a Unix timestamp
1Enter a timestamp or date. Type a Unix timestamp (seconds or milliseconds) or a date string like 2026-01-01.
2Review the conversions. ISO 8601, UTC, local time, relative time, and both Unix formats update instantly.
3Copy or download. Copy any individual value, or download the full breakdown as a file.
What is a Unix timestamp?
A Unix timestamp counts the number of seconds (or, in many APIs and databases, milliseconds) that have elapsed since January 1, 1970 UTC — the "Unix epoch." It's the most common way computers store a point in time internally, but it's not human-readable on its own, which is why converting it to a calendar date is such a common debugging task.
How Tabreon handles your data
All parsing and formatting use your browser's built-in Date object — nothing you enter is transmitted to a server.
Key features
Auto-detects Unix seconds vs. milliseconds by digit length
Accepts a plain date string as an alternative input
Shows ISO 8601, UTC, local time, and human-readable relative time
Copy-to-clipboard and file download
Common use cases
Converting a `created_at` timestamp from an API response into a readable date while debugging
Checking what a JWT's `exp` claim (a Unix timestamp) corresponds to in local time
Converting a calendar date into a Unix timestamp for a database query or API call
Common mistakes & limitations
The seconds-vs-milliseconds auto-detection is a digit-length heuristic — an unusual 13-digit seconds value (far future) could theoretically be misdetected as milliseconds.
Local time is rendered using your browser's own time zone setting; it does not let you pick an arbitrary time zone to convert into.
Frequently asked questions
No. All conversion uses your browser's built-in Date object — nothing you enter is transmitted to a server.
It uses digit length as a heuristic: numbers with 13 or more digits are treated as Unix milliseconds, shorter numbers as Unix seconds. This matches how virtually all real-world timestamps are sized for dates from 2001 onward.
Yes. Any string your browser's Date parser understands (e.g. 2026-01-01 or "Jan 1, 2026") works as input, in addition to numeric Unix timestamps.