Unix Timestamp Converter
Convert Unix timestamps to human-readable dates and back. Supports seconds and milliseconds with auto-detection. All processing happens in your browser.
How It Works
Enter Timestamp
Paste your Unix timestamp (seconds or milliseconds) in the input field.
Auto-Convert
The tool automatically detects the format and converts to human-readable date.
Copy Results
Copy any format (ISO, RFC 2822, locale) with a single click.
Features
Live Clock
See the current Unix timestamp updating in real-time.
Auto-Detection
Automatically detects if your timestamp is in seconds or milliseconds.
Multiple Formats
View results in ISO 8601, RFC 2822, locale-specific, and relative formats.
Two-Way Conversion
Convert timestamps to dates or dates back to timestamps.
What is Unix Time?
Unix time (also known as POSIX time or Epoch time) is a system for describing points in time. It represents the number of seconds that have elapsed since January 1, 1970, at 00:00:00 UTC (the "Unix Epoch").
Why is it used? Unix timestamps provide a simple, unambiguous way to represent dates and times across different systems and time zones. They're widely used in databases, APIs, log files, and programming.
Seconds vs Milliseconds: Some systems use seconds (10-digit numbers like 1705315200), while others use milliseconds (13-digit numbers like 1705315200000). This tool auto-detects which format you're using.
Common Timestamps
0946684800123100650521474836472147483647Frequently Asked Questions
A Unix timestamp (also called Epoch time or POSIX time) is the number of seconds that have elapsed since January 1, 1970, at 00:00:00 UTC. This moment is known as the 'Unix Epoch'. Timestamps provide a simple, unambiguous way to represent dates and times that works across different systems, programming languages, and time zones.
The easiest way is to count the digits: seconds timestamps are typically 10 digits (e.g., 1705315200 for dates in the 2020s), while milliseconds timestamps are 13 digits (e.g., 1705315200000). Our tool auto-detects the format automatically, but you can also manually specify which unit to use from the dropdown.
Yes, this Unix timestamp converter is completely free with no sign-up, subscriptions, or usage limits. More importantly, all processing happens entirely in your browser using JavaScript. Your data never leaves your device - nothing is sent to any server. You can even disconnect from the internet after loading the page and it will still work.
The Year 2038 problem (also called Y2K38 or the Epochalypse) occurs because many older systems store Unix timestamps as 32-bit signed integers. The maximum value is 2,147,483,647, which corresponds to January 19, 2038, at 03:14:07 UTC. After this moment, the value overflows to negative numbers, causing potential system failures. Modern systems use 64-bit integers, which won't overflow for 292 billion years.
This usually happens due to timezone differences. Unix timestamps represent a specific moment in UTC (Coordinated Universal Time). When displayed, they're converted to your local timezone, which may differ by several hours from UTC. Use the World Clock feature to see the same moment in different timezones.
The duration calculator computes the precise time difference between two dates using calendar-aware arithmetic that handles varying month lengths (28-31 days) and leap years correctly. It shows the breakdown in years, months, days, hours, minutes, and seconds, plus total values (total days, hours, etc.) for quick calculations.
The converter outputs dates in multiple formats: ISO 8601 (standard for APIs and databases), RFC 2822 (email headers), UTC string, locale-specific format (based on your browser settings), date-only (YYYY-MM-DD), time-only (HH:MM:SS), and relative time (e.g., '3 hours ago'). All formats can be copied with one click.
Yes! Negative Unix timestamps represent dates before January 1, 1970. For example, -86400 represents December 31, 1969. Our tool supports dates from 1900 to 2300. Negative timestamps are commonly encountered in historical data and databases storing birth dates or other past events.