What is a Unix timestamp and what does this converter do?

A Unix timestamp is the number of seconds (or milliseconds) since 1 January 1970 UTC. The Unix Timestamp Converter turns that epoch value into ISO 8601, UTC, and local dates, and converts dates back into epoch time.

How do I convert a date back into a Unix timestamp?

Enter a date like 2025-01-31T12:00:00Z in the date field and the Unix Timestamp Converter returns the epoch value in both seconds and milliseconds.

Does the converter use seconds or milliseconds?

Both. It auto-detects by magnitude, treating roughly 13-digit values as milliseconds, and you can also force the unit manually.

What timezones does the Unix Timestamp Converter show?

It shows both your local time and UTC for every timestamp, alongside the ISO 8601 string, so you can cross-check values across regions.

What does the relative time mean?

It expresses the timestamp compared to now, such as "in 2 days" or "3 hours ago", which is handy for spotting stale log entries.

Is my timestamp data kept private in the Unix Timestamp Converter?

Yes. The converter runs entirely in your browser with no tracking, so the values you enter never leave your device.

Unix Timestamp Converter

Convert between Unix timestamps and human dates (local + UTC).

All timestamp and date conversion happens locally in your browser, and nothing you enter is uploaded to a server.

Working with cron schedules? Try the Cron Expression Explainer.

About Unix Timestamp Converter

This unix timestamp converter turns epoch values into readable dates and converts dates back into Unix time. Paste a timestamp in seconds or milliseconds and it auto-detects the unit by magnitude (around 13 digits is treated as milliseconds), then shows the ISO 8601 string, UTC time, your local time, and a relative phrase like "3 hours ago". You can also enter a date such as 2025-01-31T12:00:00Z and get back both the seconds and milliseconds epoch, making it a fast epoch converter for unix time to date and back. A live clock shows the current time as it ticks. It is built for developers, QA engineers, and anyone debugging logs, APIs, or database fields. Everything is processed locally in your browser, so your data never leaves your device.

Features

Converts Unix timestamps in seconds or milliseconds to human-readable dates
Auto-detects the unit by magnitude, or lets you force seconds or milliseconds
Shows ISO 8601, UTC, and your local time side by side
Displays relative time such as "in 2 days" or "5 minutes ago"
Converts a date string back into both seconds and millisecond timestamps
Live current-time display that updates as the clock ticks
Flags out-of-range timestamps and unparseable dates with clear messages
One-click copy for any converted value

How to use the Unix Timestamp Converter

Paste a Unix timestamp into the input box, or type a date like 2025-01-31T12:00:00Z.
Let the tool auto-detect seconds or milliseconds, or pick the unit manually.
Read the ISO, UTC, local, and relative-time results.
Click copy next to any value to grab it for your code or logs.

Example

Input

1706700000

Output

ISO:   2024-01-31T11:20:00.000Z
UTC:   Wed, 31 Jan 2024 11:20:00 GMT
Local: 1/31/2024, 11:20:00 AM
Unit:  seconds

A 10-digit value is detected as seconds and expanded to ISO, UTC and local time.

Common errors & troubleshooting

A 13-digit millisecond timestamp is read as seconds, giving a date thousands of years in the future. — Force the unit to milliseconds, or trim the trailing three digits if you meant seconds.
Entering a non-numeric value shows "Enter a numeric timestamp." — Use only digits (and an optional leading minus) in the timestamp box; put text dates in the date field instead.
A date string fails to parse with a "Could not parse date" message. — Use an unambiguous format like 2025-01-31 or 2025-01-31T12:00:00Z.
A huge timestamp returns "Timestamp is out of range." — Check the unit; a milliseconds value entered as seconds (or extra digits) can push the date past JavaScript's supported range.
Local time looks off by several hours compared to a colleague's. — Compare the UTC value instead, since local time reflects your own machine's timezone.

Frequently asked questions

What is a Unix timestamp and what does this converter do?: A Unix timestamp is the number of seconds (or milliseconds) since 1 January 1970 UTC. The Unix Timestamp Converter turns that epoch value into ISO 8601, UTC, and local dates, and converts dates back into epoch time.
How do I convert a date back into a Unix timestamp?: Enter a date like 2025-01-31T12:00:00Z in the date field and the Unix Timestamp Converter returns the epoch value in both seconds and milliseconds.
Does the converter use seconds or milliseconds?: Both. It auto-detects by magnitude, treating roughly 13-digit values as milliseconds, and you can also force the unit manually.
What timezones does the Unix Timestamp Converter show?: It shows both your local time and UTC for every timestamp, alongside the ISO 8601 string, so you can cross-check values across regions.
What does the relative time mean?: It expresses the timestamp compared to now, such as "in 2 days" or "3 hours ago", which is handy for spotting stale log entries.
Is my timestamp data kept private in the Unix Timestamp Converter?: Yes. The converter runs entirely in your browser with no tracking, so the values you enter never leave your device.

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