What is a Unix epoch timestamp?

A Unix epoch timestamp represents the number of seconds that have elapsed since January 1, 1970, 00:00:00 UTC. It is widely used in computing for tracking time, scheduling events, and storing timestamps in databases. For example, 1700000000 represents a specific moment in November 2023.

What is the difference between seconds, milliseconds, and nanoseconds?

Seconds are used by older Unix APIs. Milliseconds (1000x) are used by most modern APIs and JavaScript. Nanoseconds (1 billion x) are used in high-performance systems like Go and certain databases. The tool auto-detects the magnitude of your input.

How does timezone affect epoch conversion?

Epoch timestamps are always in UTC — they represent a single moment regardless of timezone. When converting to human-readable format, the timezone determines how the date is displayed. The same epoch shows different local times in New York vs Tokyo.

What is the Y2038 problem?

The Y2038 problem occurs when 32-bit signed Unix timestamps overflow on January 19, 2038 at 03:14:07 UTC (epoch 2147483647). After this, 32-bit systems wrap to negative values. Modern 64-bit systems are unaffected.

Does this tool process data client-side?

Yes. All conversions happen in your browser using JavaScript. No data is sent to any server. The tool uses 64-bit floating-point numbers, which safely represent timestamps up to approximately the year 285,428.

Encoding & Data

Epoch & Timestamp

Free online Unix timestamp converter. Convert epoch to date or date to epoch with support for seconds, milliseconds, and nanoseconds. Batch convert multiple timestamps, view a live epoch clock, and output in ISO 8601, RFC 2822, or locale format. Perfect for debugging JWT exp claims, cron jobs, and database timestamps. 100% client-side.

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Quick reference

Category: Encoding & Data
Runs in: Browser
Data stored: Nothing
Price: Free
Sign-up: Not needed

Browse categories

All features

Epoch to human-readable date conversion
Date to epoch timestamp conversion
Seconds, milliseconds, and nanoseconds support
ISO 8601, RFC 2822, and locale formats
Live epoch clock and relative time
Batch and timezone-aware conversion

What you can do

Convert epoch to human date

Paste a Unix timestamp (seconds, milliseconds, or nanoseconds) and instantly see the human-readable date in ISO 8601, RFC 2822, and locale formats.

Convert date to epoch

Pick a date and time to get the corresponding Unix timestamp in seconds, milliseconds, and nanoseconds.

View a live epoch clock

Watch the current Unix timestamp tick in real time. Useful for debugging time-sensitive systems or learning how epoch time works.

Batch convert timestamps

Paste multiple epoch timestamps at once to convert them all to human-readable dates in a single operation.

Check relative time

See how long ago or how far in the future a timestamp is relative to now. Useful for debugging expiring tokens or scheduled jobs.

Private by design

Client-side
No sign-up
Free

Epoch & Timestamp runs entirely in your browser tab. No data is uploaded, no server processes your input, and no account is required.

Specifications

Precision: Seconds, milliseconds, nanoseconds
Output formats: ISO 8601, RFC 2822, locale, relative time
Input: Epoch number or date picker
Features: Live clock, batch conversion, timezone-aware
Epoch: January 1, 1970 00:00:00 UTC
Processing: 100% client-side, works offline

Frequently asked questions

Related keywords

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