What is the difference between epoch seconds and epoch milliseconds?

Epoch seconds count the number of seconds since January 1, 1970 UTC and are used by Unix systems, Python, PHP, and most server-side languages. Epoch milliseconds count thousandths of a second and are the default in JavaScript (Date.now()), Java (System.currentTimeMillis()), and many REST APIs. This tool works with milliseconds as the primary unit and shows the seconds equivalent alongside it.

How do I know if my timestamp is in seconds or milliseconds?

Count the digits. A current epoch in seconds has 10 digits (around 1.7 billion). A current epoch in milliseconds has 13 digits (around 1.7 trillion). If your value has 10 digits, multiply by 1000 before entering it here, or use our Unix Timestamp Converter which handles seconds natively.

Why does the local time differ from UTC?

UTC is the universal reference time with no timezone offset. Your local time reflects your system timezone setting, which may be hours ahead or behind UTC depending on your geographic location and daylight saving rules. This tool shows both so you can verify which representation you need.

What is the Y2K38 problem shown in the quick reference?

The Y2K38 bug affects systems that store Unix timestamps as 32-bit signed integers. The maximum value (2,147,483,647) corresponds to January 19, 2038 at 03:14:07 UTC. After this moment, 32-bit timestamps overflow to negative values, potentially causing date calculations to jump back to 1901. Most modern systems use 64-bit timestamps which last billions of years.

Is epoch time affected by time zones or daylight saving?

No. Epoch timestamps are always relative to UTC and are timezone-agnostic. The same epoch value represents the exact same moment in time worldwide. Time zones only affect how that moment is displayed as a human-readable date. This is why epoch timestamps are preferred for storing and transmitting time data between systems in different locations.

Can I convert negative epoch values?

This tool accepts non-negative values only (0 and above), covering dates from January 1, 1970 onwards. Negative epoch values represent dates before 1970 and are supported by some systems but can cause compatibility issues. For pre-1970 dates, most applications use calendar date formats rather than epoch timestamps.

Free tool

Epoch converter

Convert epoch milliseconds to human-readable dates and back. Millisecond precision, UTC and local timezone, live counter, and instant copy.

100% free
No sign-up
No limits
Instant results

Current epoch (live)

1788743623688ms

seconds:1788743623

Epoch milliseconds to date

Date to epoch milliseconds

Quick reference

What this tool does

Millisecond-precision epoch conversion
Two-way: epoch to date and date to epoch
UTC and local timezone side by side
Live ticking epoch counter
Quick reference for common epoch values
100% browser — no server calls

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The short version

What is Epoch Converter?

An epoch converter is a tool that translates Unix epoch timestamps into human-readable dates and vice versa.

The Unix epoch is the number of seconds (or milliseconds) that have elapsed since January 1, 1970 00:00:00 UTC, which is the reference point used by most programming languages and operating systems to represent time internally. This tool focuses on millisecond precision, which is the format used by JavaScript's Date.now(), Java's System.currentTimeMillis(), and many modern APIs that need sub-second accuracy. You can paste any epoch value in milliseconds to see the corresponding date in UTC, your local timezone, and ISO 8601 format, along with a relative description like '3 hours ago.' The reverse conversion lets you pick a date and time to get the epoch value in both milliseconds and seconds. A live ticking counter shows the current epoch in real time, and a quick reference table lists common epoch milestones like the Unix epoch origin, Y2K, and the Y2K38 overflow bug date. All conversions happen entirely in your browser with zero server interaction.

Step by step

How to use Epoch Converter

1
Convert epoch to date
Paste an epoch value in milliseconds into the input field or click Now to use the current timestamp. The tool instantly shows the date in UTC, your local timezone, ISO 8601 format, and as a relative time description. Both seconds and milliseconds epoch values are displayed.
2
Convert date to epoch
Use the date-time picker to select a specific date and time, or click Now to fill in the current moment. The tool outputs the corresponding epoch in milliseconds and seconds, plus the ISO 8601 representation.
3
Use quick references and copy
Click any value in the quick reference table to load common epoch milestones like the Unix origin, Y2K, or Y2K38 bug. Every output field has a copy button for one-click clipboard access.

What's inside

Everything this tool
does for you

Millisecond-precision epoch to date conversion with instant results
Reverse date to epoch conversion using a native date-time picker
UTC and local timezone displayed side by side for every conversion
ISO 8601 output for standards-compliant timestamp formatting
Relative time output showing human-friendly descriptions like "3 hours ago"
Live ticking epoch counter showing the current timestamp in real time
Quick reference table with common epoch milestones and one-click loading
Copy buttons on every output field for instant clipboard access

Keep going

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Questions

Frequently asked questions

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What is Epoch Converter?

How to use Epoch Converter

Convert epoch to date

Convert date to epoch

Use quick references and copy

Everything this tooldoes for you

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Unix Timestamp Converter

Number Base Converter

Temperature Converter

Unit Converter

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Roman Numeral Converter

Frequently asked questions

What is the difference between epoch seconds and epoch milliseconds?

How do I know if my timestamp is in seconds or milliseconds?

Why does the local time differ from UTC?

What is the Y2K38 problem shown in the quick reference?

Is epoch time affected by time zones or daylight saving?

Can I convert negative epoch values?

This tool fixed one thing.Now fix the whole site.

Everything this tool
does for you

This tool fixed one thing.
Now fix the whole site.