Timestamp Converter

Unix timestamp ↔ human-readable date/time

Current Unix Timestamp

—

Timestamp → Date/Time

Date/Time → Timestamp

About this tool

A Unix timestamp is the number of seconds (or milliseconds) elapsed since 1970-01-01 00:00:00 UTC. It's the lingua franca of timestamps in databases, log files, APIs, and programming languages — easy to compare, easy to sort, time-zone agnostic.

This tool converts Unix timestamps to human-readable date/time and back, in both seconds and milliseconds. All conversion happens in your browser using the native Date API.

How to use

Timestamp → date

Paste a numeric timestamp.
Pick Seconds or Milliseconds depending on the source (10 digits ≈ seconds, 13 digits ≈ milliseconds).
Read the local time, UTC time, and ISO 8601 representations side-by-side.

Date → timestamp

Pick a date and time, or click Now to use the current moment.
Both seconds and milliseconds outputs are shown — copy whichever your system expects.

Examples

Seconds → date

Input

1700000000

Output

Local: 2023-11-15 06:13:20
UTC:   2023-11-14 22:13:20
ISO:   2023-11-14T22:13:20.000Z

Milliseconds → date

Input

1700000000000

Output

Local: 2023-11-15 06:13:20.000
UTC:   2023-11-14 22:13:20.000
ISO:   2023-11-14T22:13:20.000Z

Frequently asked questions

Seconds or milliseconds — how do I tell?

By length. Today's timestamps are around 10 digits in seconds and 13 digits in milliseconds. If your number has 10 digits, it's seconds; 13 digits, it's milliseconds. JavaScript Date uses milliseconds; most Unix CLIs and Linux APIs use seconds.

What's the Y2K38 problem?

On 2038-01-19 03:14:07 UTC, a 32-bit signed integer used to store seconds-since-epoch overflows. Modern 64-bit systems and JavaScript (which uses double-precision floats) aren't affected, but legacy embedded systems and old database columns may need migration.

How are time zones handled?

Unix timestamps are always UTC by definition — no time zone is encoded. The 'Local' column above is rendered using your browser's time zone for convenience. The actual instant is the same everywhere.

Does it support negative timestamps?

Yes — values before 1970 are negative. -86400 means one day before the epoch (1969-12-31 UTC). Useful for historical date math.

Why does the local time look wrong?

Almost always a time-zone misunderstanding. Check your system clock and time zone setting. The ISO and UTC columns are the source of truth — Local is just your browser's interpretation.