Unix Timestamp Converter

Convert Unix timestamps to human-readable dates and dates back to timestamps in seconds, milliseconds, UTC, local time, and ISO 8601.

For this tool, processing runs locally in your browser and data is not sent to the server.

Unix Timestamp Converter is a free online tool that converts Unix timestamps to readable dates and dates back to Unix timestamps. It supports seconds and milliseconds, and shows local time, UTC, ISO 8601, RFC 3339, and Unix formats. The tool is useful for server logs, API responses, JWT exp/iat/nbf claims, and JavaScript Date.now(). Processing is done locally in the browser.

What it does

Output

Processing

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How to use

Paste a Unix timestamp in seconds or milliseconds, or a date in ISO format.
Leave Auto mode or manually choose a conversion direction.
Check the result in local time, UTC, ISO 8601, Unix seconds, and Unix milliseconds.
Copy the result for logs, API payloads, JWT exp/iat/nbf, backend debugging, or documentation.

More about this tool

Unix Timestamp Converter translates Unix time to a readable date and back. The tool recognizes timestamps in both seconds and milliseconds, and shows local time, UTC, ISO 8601, RFC 3339, Unix seconds, and Unix milliseconds. This is useful when working with server logs, API responses, JWT claims such as exp, iat, and nbf, webhook payloads, databases, and JavaScript Date.now().

The converter automatically detects whether the input is a timestamp or a date string, but you can also select the direction manually for clarity.

All conversion is done locally in the browser. No data is sent to the server.

Runs in the browser
Data is not sent to the server
Converts Unix timestamp to a date
Converts a date back to a timestamp
Supports seconds and milliseconds
Shows local time, UTC, and ISO 8601
Useful for logs, APIs, JWT claims, and backend debugging
No registration required

Frequently Asked Questions

What is a Unix timestamp?

A Unix timestamp is the number of seconds or milliseconds elapsed since 1970-01-01T00:00:00Z. This format is widely used in APIs, logs, databases, and JWT tokens.

What is the difference between seconds and milliseconds?

A Unix timestamp in seconds typically has about 10 digits, for example 1700000000. A timestamp in milliseconds typically has about 13 digits, for example 1700000000000.

How do I convert a timestamp to a date?

Paste the timestamp into the value field and choose Timestamp → Date mode, or leave Auto. The tool will show local time, UTC, and ISO format.

How do I get a timestamp from a date?

Paste a date such as 2024-01-01 or 2024-01-01T00:00:00Z and the tool will show the corresponding Unix seconds and Unix milliseconds.

Why does local time differ from UTC?

UTC is a universal reference time with no local offset. Local time depends on the browser timezone or the selected UTC offset.

Is the tool useful for JWT exp claims?

Yes. The exp, iat, and nbf claims in JWTs are stored as Unix timestamps in seconds. The converter helps you quickly understand when a token expires.

What is JavaScript Date.now()?

Date.now() returns the current Unix timestamp in milliseconds, which is why it produces a longer number than a seconds-based timestamp.

Is my data sent to the server?

No. Values are processed locally in the browser and are not sent to the server.

Do I need to register?

No. The tool works immediately without registration.

How to use

Paste a Unix timestamp in seconds or milliseconds, or a date in ISO format.

Leave Auto mode or manually choose a conversion direction.

Check the result in local time, UTC, ISO 8601, Unix seconds, and Unix milliseconds.

Copy the result for logs, API payloads, JWT exp/iat/nbf, backend debugging, or documentation.

More about this tool

The converter automatically detects whether the input is a timestamp or a date string, but you can also select the direction manually for clarity.

All conversion is done locally in the browser. No data is sent to the server.

Runs in the browser
Data is not sent to the server
Converts Unix timestamp to a date
Converts a date back to a timestamp
Supports seconds and milliseconds
Shows local time, UTC, and ISO 8601
Useful for logs, APIs, JWT claims, and backend debugging
No registration required

Frequently Asked Questions

What is a Unix timestamp?

A Unix timestamp is the number of seconds or milliseconds elapsed since 1970-01-01T00:00:00Z. This format is widely used in APIs, logs, databases, and JWT tokens.

What is the difference between seconds and milliseconds?

A Unix timestamp in seconds typically has about 10 digits, for example 1700000000. A timestamp in milliseconds typically has about 13 digits, for example 1700000000000.

How do I convert a timestamp to a date?

Paste the timestamp into the value field and choose Timestamp → Date mode, or leave Auto. The tool will show local time, UTC, and ISO format.

How do I get a timestamp from a date?

Paste a date such as 2024-01-01 or 2024-01-01T00:00:00Z and the tool will show the corresponding Unix seconds and Unix milliseconds.

Why does local time differ from UTC?

UTC is a universal reference time with no local offset. Local time depends on the browser timezone or the selected UTC offset.

Is the tool useful for JWT exp claims?

Yes. The exp, iat, and nbf claims in JWTs are stored as Unix timestamps in seconds. The converter helps you quickly understand when a token expires.

What is JavaScript Date.now()?

Date.now() returns the current Unix timestamp in milliseconds, which is why it produces a longer number than a seconds-based timestamp.

Is my data sent to the server?

No. Values are processed locally in the browser and are not sent to the server.

Do I need to register?

No. The tool works immediately without registration.