Unix Timestamp Converter

Convert Unix timestamps to human-readable dates and times, and convert any date back to a Unix timestamp in seconds or milliseconds.

What is a Unix timestamp

A Unix timestamp (also called epoch time or POSIX time) is the number of seconds that have elapsed since 00:00:00 UTC on 1 January 1970, known as the Unix epoch. It is the most widely used system for representing time in software because it is a simple integer, timezone-independent, and easy to store, compare, and calculate with.

Unix time vs milliseconds

Most systems use seconds (10-digit number in 2024). JavaScript, Java, and some APIs use milliseconds (13-digit number). For example, 2024-01-01 00:00:00 UTC = 1704067200 seconds = 1704067200000 milliseconds. This tool automatically detects whether your input is in seconds or milliseconds.

Timezone handling

Unix timestamps are always in UTC (Coordinated Universal Time). When converting to a local date, this tool shows both the UTC representation and the local date/time based on your browser's timezone setting. Always check which timezone you need when reading API responses that return timestamps.

Common uses

• Reading API responses that return Unix timestamps
• Debugging database records with timestamp columns
• Checking token expiry times in JWT authentication
• Converting log file timestamps to readable dates
• Scheduling and calculating time differences in code

How to use Unix Timestamp Converter

1. Enter a Unix timestamp in the top section to convert it to a readable date.
2. Click Now to use the current time automatically.
3. Use the bottom section to convert a date/time back to a Unix timestamp.
4. Click any copy button to copy individual values.

Why this tool is useful

• Auto-detects seconds vs milliseconds input.
• Shows UTC, local, ISO, and formatted date versions.
• Convert both directions — timestamp to date and date to timestamp.
• Instant result with no submit needed.

Example use cases

Timestamp to date: 1704067200 → 2024-01-01 00:00:00 UTC

Date to timestamp: 2025-06-23 12:00 → 1750680000 seconds

Frequently asked questions

Is this tool free to use?

Yes. This tool is completely free to use on Smartweb.tools, with no sign-up, subscription or hidden charges.

What is a Unix timestamp?

A Unix timestamp is the number of seconds that have passed since 1 January 1970 (UTC), a common way for computers to store dates and times.

Can I convert both ways?

Yes. You can convert a Unix timestamp into a human-readable date and time, and convert a date back into a timestamp.

Does it work on mobile?

Yes. The tool is responsive and works in modern browsers on phones, tablets and desktops.

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