What is a Unix Timestamp?
Handling dates and times in software development is notoriously difficult. A timestamp like "March 15th, 2024 at 3:00 PM" is completely ambiguous. Is that 3:00 PM in New York, London, or Tokyo? Does it account for Daylight Saving Time?
To solve this chaos, the computing world relies on the Unix Epoch.
A Unix Timestamp is a single integer that represents the total number of seconds (or milliseconds) that have elapsed since January 1st, 1970 at 00:00:00 UTC. Because it is a fixed, timezone-independent number, computers can use it to store and compare exact moments in time with flawless accuracy.
The Problem with Human Readability
While Unix Timestamps (e.g., 1710514800) are perfect for databases and APIs, they are completely meaningless to humans. You cannot look at a 10-digit number and know what day of the week it represents.
A Timestamp Converter is an essential utility for developers and system administrators. When debugging a server log or inspecting an API payload, you frequently need to translate a Unix integer back into a human-readable, localized date format.
Seconds vs. Milliseconds
The most common mistake developers make when working with timestamps is confusing seconds and milliseconds.
- Seconds (10 digits): The standard Unix format used by most backend systems, databases (like MySQL), and languages like PHP or Python. Example:
1710514800. - Milliseconds (13 digits): The standard format used by JavaScript and the modern web. It multiplies the Unix timestamp by 1000 to offer sub-second precision. Example:
1710514800000.
If you accidentally pass a 10-digit timestamp into a JavaScript Date() object without multiplying it by 1000, your application will calculate the date as being somewhere in early 1970.
Absolute Client-Side Accuracy
Calculating complex dates, leap years, and local timezone offsets requires immense precision.
Our Timestamp Converter runs entirely within your browser using the native JavaScript Date API. This allows the tool to instantly read your computer's local timezone settings and automatically translate cold Unix integers into your exact local time, without ever sending your sensitive server logs to an external API.
How to use the Timestamp Converter
- 1
Paste a Unix timestamp — seconds or milliseconds are detected automatically.
- 2
Or pick a date and time to get its timestamp.
- 3
Copy any format: ISO 8601, RFC 2822, relative time and more.
Features
- Live epoch clock
- See the current Unix time ticking in real time.
- Auto-detect units
- Handles seconds, milliseconds and microseconds.
- Time zones
- View the date in any IANA time zone.
- Many formats
- ISO 8601, RFC 2822, UTC, local and relative time.
Frequently asked questions
What is a Unix timestamp?
A Unix timestamp is the number of seconds elapsed since 00:00:00 UTC on January 1, 1970 (the Unix epoch), not counting leap seconds.
Seconds or milliseconds?
Most Unix systems use seconds (10 digits today), while JavaScript and many APIs use milliseconds (13 digits). This tool detects which one you entered.
Are my timestamps uploaded to a server?
No. All processing happens locally in your browser using JavaScript and WebAssembly. Your timestamps never leave your device, and nothing is stored or logged.