Unix Timestamp Converter — Convert Timestamps Online

Input (Unix timestamp or date string)

Converted Output

What is a Unix Timestamp?

A Unix timestamp (also called epoch time) is the number of seconds elapsed since January 1, 1970, at 00:00:00 UTC — a standard defined in POSIX and used practically everywhere in computing. When you call Date.now() in JavaScript, log a server event in Python with time.time(), or inspect a database record's created_at field, you're dealing with epoch time. The problem? 1700000000 tells you nothing at a glance. This tool converts it to a format you can actually read — and converts readable date strings back to timestamps when you need the raw number. Everything runs in your browser; the Unix time Wikipedia article goes deep on the history if you're curious. For date arithmetic and formatting in code, the ECMAScript Date specification is the authoritative reference. Need to work with timestamps in shell scripts? The GNU coreutils date command is your friend.

This tool converts Unix timestamps (in seconds or milliseconds) to human-readable date formats, and also converts date strings back to Unix timestamps.

How to Use

Enter a timestamp or date

Paste a Unix timestamp (e.g. 1700000000) or a date string (e.g. 2023-11-14T22:13:20Z) into the input panel.

See all formats instantly

The tool auto-detects whether you entered a timestamp or date string and shows all relevant conversions immediately.

Use Current Time

Click "Use Current Time" to populate the input with the current Unix timestamp and see its conversions.

Conversion Examples

Example: Unix timestamps

Unix timestamp (seconds):

1700000000

Converted to human-readable:

UTC:   2024-03-28 00:00:00
ISO:   2024-03-28T00:00:00.000Z
Local: Thu Mar 28 2024 00:00:00 GMT+0000

Frequently Asked Questions

What is the difference between Unix time in seconds and milliseconds?

Unix time in seconds is the classic epoch format (e.g. 1700000000). Milliseconds multiply that by 1000 (e.g. 1700000000000), which is what JavaScript's Date.now() returns. This tool auto-detects which one you're using.

How do I detect if a number is seconds or milliseconds?

Count the digits. Numbers with 13 or more digits are typically milliseconds; numbers with 10 or fewer digits are typically seconds. A 10-digit timestamp like 1700000000 represents a date in 2023; a 13-digit one is the same moment in milliseconds.

What date formats can I enter?

ISO 8601 strings (e.g. 2023-11-14T22:13:20Z), common date strings like November 14, 2023, or any format the JavaScript Date constructor accepts. ISO 8601 is the safest bet across all environments.

Does this tool send my timestamps to a server?

No. All conversion logic runs entirely in your browser. Nothing is uploaded, logged, or tracked. It's safe to paste timestamps from production logs or private systems.

What is epoch time and why does it start at 1970?

The Unix epoch — January 1, 1970, 00:00:00 UTC — was chosen when Unix was being developed. It's an arbitrary but universally agreed-upon starting point. Every Unix timestamp is the number of seconds since that moment. Dates before 1970 are represented as negative numbers.