Converters

Timestamp Converter

Convert Unix timestamps to human-readable dates and back

Timestamp / Date Input

Timezone:

Use UTC

Enter a Unix timestamp (seconds or milliseconds), ISO 8601 date, or human-readable date to convert

About

Timestamp converter with auto-detection of Unix (seconds/milliseconds), ISO 8601, and human-readable date formats. Converts to 11 different output formats including Unix seconds, Unix milliseconds, ISO 8601, RFC 2822, UTC string, locale date/time strings, relative time ("2 hours ago"), and Japanese/Chinese date formats. Features a timezone selector, Now button, countdown timer to a target timestamp, diff calculator between two timestamps, and leap year detection.

Timestamps appear in many formats across APIs, databases, and logs — converting between them manually is tedious and error-prone. This tool detects the input format automatically and provides every common output format in one view.

Who should use this tool?

Backend developers, API integrators, database administrators, QA engineers, and anyone working with time data across different systems and timezones.

Common use cases

Convert a Unix timestamp from an API response to a human-readable date for debugging
Generate an ISO 8601 string from a local date for a JSON payload
Calculate the time difference between two Unix timestamps in seconds/minutes/hours/days
Count down to a specific date (e.g., product launch) to see remaining time
Check if a given year is a leap year for date validation logic
Convert a timestamp between timezones (e.g., UTC to Asia/Tokyo)

How to Use

Paste or type a timestamp into the input field — the tool auto-detects Unix (seconds/milliseconds), ISO 8601, or human-readable format.

View the 11 output formats in the results grid, each labeled with its format name.

Select a target timezone from the dropdown to convert all outputs to that timezone.

Click the Now button to insert the current Unix timestamp (in seconds) into the input.

Use the Diff tab to enter two timestamps and see the difference in seconds, minutes, hours, days, and weeks.

Switch to the Countdown tab to set a future timestamp and watch a live countdown timer.

Examples

Input: "1735689600" (auto-detected as Unix seconds) → Outputs include: ISO 8601 "2025-01-01T00:00:00.000Z", RFC 2822 "Wed, 01 Jan 2025 00:00:00 +0000", relative "1 year ago"

Input: "2025-12-25T14:30:00" with timezone America/New_York → Outputs include: Unix seconds 1735677000, Japan time "2025-12-26 04:30:00 JST"

Best Practices

Always verify auto-detected format — Unix seconds vs. milliseconds (10 digits vs. 13 digits) can be ambiguous
Use the Now button for quick insertion of the current time when testing
Use the Diff calculator to validate time-based business logic like expiry windows
Select the correct timezone before converting to avoid off-by-one day errors
Check leap year detection when writing date validation for birthdates or contract dates

Common Mistakes

Confusing Unix seconds (10 digits) with Unix milliseconds (13 digits) — using the wrong unit shifts the date by decades
Assuming ISO 8601 always includes timezone offset — local-time ISO strings lack "Z" or offset
Forgetting that JavaScript Date.getTime() returns milliseconds, not seconds
Using the wrong timezone for daylight saving date ranges — the tool applies DST rules automatically
Misreading relative time for future dates — "in 2 hours" vs. "2 hours ago"

FAQ

What is the difference between Unix seconds and Unix milliseconds? Unix seconds = seconds since epoch (Jan 1, 1970); milliseconds = that value × 1000. A typical 10-digit number is seconds; a 13-digit number is milliseconds.

Does the tool handle timezone abbreviations like PST/EST? Use IANA timezone names (e.g., America/Los_Angeles)

ambiguous abbreviations are not supported.

How accurate is the countdown timer? The countdown refreshes every second and is synchronized with the system clock.

Can I convert dates before 1970? Yes

Unix timestamps can represent dates from 1901 to 2038 (32-bit) and beyond (64-bit timestamps handled).

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Learning Resources

Dive deeper with our comprehensive guides and tutorials.

Timestamp Converter - Beginner's Guide

5 min read

Timestamp Converter Advanced Techniques

8 min read

Timestamp Converter

Convert Unix timestamps to human-readable dates and back

Timestamp / Date Input

Timezone:

Use UTC

Enter a Unix timestamp (seconds or milliseconds), ISO 8601 date, or human-readable date to convert

About

Who should use this tool?

Backend developers, API integrators, database administrators, QA engineers, and anyone working with time data across different systems and timezones.

Common use cases

Convert a Unix timestamp from an API response to a human-readable date for debugging
Generate an ISO 8601 string from a local date for a JSON payload
Calculate the time difference between two Unix timestamps in seconds/minutes/hours/days
Count down to a specific date (e.g., product launch) to see remaining time
Check if a given year is a leap year for date validation logic
Convert a timestamp between timezones (e.g., UTC to Asia/Tokyo)

How to Use

Paste or type a timestamp into the input field — the tool auto-detects Unix (seconds/milliseconds), ISO 8601, or human-readable format.

View the 11 output formats in the results grid, each labeled with its format name.

Select a target timezone from the dropdown to convert all outputs to that timezone.

Click the Now button to insert the current Unix timestamp (in seconds) into the input.

Use the Diff tab to enter two timestamps and see the difference in seconds, minutes, hours, days, and weeks.

Switch to the Countdown tab to set a future timestamp and watch a live countdown timer.

Examples

Input: "1735689600" (auto-detected as Unix seconds) → Outputs include: ISO 8601 "2025-01-01T00:00:00.000Z", RFC 2822 "Wed, 01 Jan 2025 00:00:00 +0000", relative "1 year ago"

Input: "2025-12-25T14:30:00" with timezone America/New_York → Outputs include: Unix seconds 1735677000, Japan time "2025-12-26 04:30:00 JST"

Best Practices

Always verify auto-detected format — Unix seconds vs. milliseconds (10 digits vs. 13 digits) can be ambiguous

Use the Now button for quick insertion of the current time when testing

Use the Diff calculator to validate time-based business logic like expiry windows

Select the correct timezone before converting to avoid off-by-one day errors

Check leap year detection when writing date validation for birthdates or contract dates

Common Mistakes

Confusing Unix seconds (10 digits) with Unix milliseconds (13 digits) — using the wrong unit shifts the date by decades

Assuming ISO 8601 always includes timezone offset — local-time ISO strings lack "Z" or offset

Forgetting that JavaScript Date.getTime() returns milliseconds, not seconds

Using the wrong timezone for daylight saving date ranges — the tool applies DST rules automatically

Misreading relative time for future dates — "in 2 hours" vs. "2 hours ago"

FAQ

Does the tool handle timezone abbreviations like PST/EST? Use IANA timezone names (e.g., America/Los_Angeles)

ambiguous abbreviations are not supported.

How accurate is the countdown timer? The countdown refreshes every second and is synchronized with the system clock.

Can I convert dates before 1970? Yes

Unix timestamps can represent dates from 1901 to 2038 (32-bit) and beyond (64-bit timestamps handled).

Timestamp Converter

About

Who should use this tool?

Common use cases

How to Use

Examples

Best Practices

Common Mistakes

FAQ

Related Tools

Same Category — Converters

JSON to CSV Converter

CSV to JSON Converter

JSON to TypeScript

Markdown to HTML Converter

Popular Tools

JSON Formatter

Base64 Encoder/Decoder

JWT Decoder

Learning Resources

Share

Timestamp Converter

About

Who should use this tool?

Common use cases

How to Use

Examples

Best Practices

Common Mistakes

FAQ

Related Tools

Same Category — Converters

JSON to CSV Converter

CSV to JSON Converter

JSON to TypeScript

Markdown to HTML Converter

Popular Tools

JSON Formatter

Base64 Encoder/Decoder

JWT Decoder

Learning Resources

Share