Unix Epoch Time to Date: A Developer's Converter Guide

Unix epoch time is the number of seconds elapsed since 00:00:00 UTC on 1 January 1970, and this converter turns any epoch value into a readable date — or a date back into epoch — in seconds, milliseconds or microseconds. A live current epoch ticks at the top so you always have a reference point.

This guide explains the epoch, the difference between the three precisions, the Year 2038 problem, and why negative and time-zone-independent values behave the way they do.

Why work with a dedicated epoch tool

General date tools blur the units, but Unix systems, JavaScript and databases each count time differently — seconds, milliseconds and microseconds respectively. When you are debugging cron jobs, cache TTLs, log files or database records, mixing those up produces dates that are wildly off. An epoch-focused converter that lets you set the unit explicitly removes that ambiguity and gives you the exact instant every time.

How to convert epoch time in your browser

1. Read or copy the live current Unix epoch shown at the top.
2. Choose your unit: seconds, milliseconds or microseconds.
3. Paste an epoch value to convert it into local, UTC and ISO 8601 dates.
4. Or pick a date and time to get its epoch value, then copy it.
5. Use the reference table for the epoch at the start of today, this month and this year.

Seconds vs milliseconds vs microseconds

All three name the same instant at different resolutions. This table shows how they line up:

Unit	Digits (today)	Typical source
Seconds	10	Unix tools, most APIs
Milliseconds	13	JavaScript Date.now()
Microseconds	16	PostgreSQL and similar databases

To move between them, multiply or divide by 1000. Getting the unit right is the single most common fix when a converted date looks wrong.

Key features

• Live ticking current Unix epoch with copy.
• Explicit seconds, milliseconds or microseconds units.
• Epoch to date and date to epoch conversion.
• Local, UTC and ISO 8601 output formats.
• Reference table for the start of today, this month and this year.
• 100% client-side and offline-capable — safe for production values.

Try the Unix Timestamp Converter now — it's free and runs entirely in your browser.

Frequently asked questions

What is the Unix epoch?

It is 00:00:00 UTC on 1 January 1970, the zero point from which Unix time counts. A Unix timestamp is the number of seconds — or milliseconds or microseconds — since that moment, ignoring leap seconds.

What is the difference between epoch seconds, milliseconds and microseconds?

They measure the same instant at different precisions. Unix tools use 10-digit seconds, JavaScript returns 13-digit milliseconds, and some databases store 16-digit microseconds. Multiply or divide by 1000 to convert.

What is the Year 2038 problem?

Systems storing Unix time in a signed 32-bit integer overflow on 19 January 2038 at 03:14:07 UTC, when the count passes 2,147,483,647. Modern 64-bit systems are unaffected, but old embedded devices and file formats may still be at risk.

Does Unix time change with my time zone?

No. Unix time is always counted in UTC, so one instant has the same epoch value everywhere. Only the readable conversion differs by zone, which is why the tool shows both local time and UTC.

Can a Unix timestamp be negative?

Yes. Negative values are moments before 1 January 1970 — for example -86400 is 31 December 1969 at 00:00 UTC. JavaScript and most languages handle negative epochs correctly.

Related free tools

• Timestamp Converter — auto-detects seconds versus milliseconds.
• Time Zone Converter — convert times across world zones.
• Date Difference Calculator — measure the gap between two dates.
• JWT Decoder — read token claims including epoch expiry.

Built by ByteVancer

ByteTools is a free product of ByteVancer, a software and web development studio that builds web apps, SaaS platforms and custom software for businesses. Need backend engineering or developer tooling built for your team? Explore ByteVancer's services or get in touch to start a project.