What is a Unix timestamp?

A Unix timestamp counts seconds (or milliseconds) elapsed since January 1, 1970 00:00:00 UTC, known as the Unix epoch. It is a timezone-independent way to represent a single moment in time used by databases, APIs, and operating systems.

Why does my timestamp show the wrong date?

The most common cause is mixing seconds and milliseconds — a seconds value read as milliseconds lands in January 1970, while milliseconds read as seconds lands tens of thousands of years ahead. Toggle the unit switch and convert again.

What is the difference between UTC and local time here?

UTC is the universal reference time with no offset, while local time applies your device's timezone and daylight-saving rules. The same timestamp can fall on different calendar days in each, which is why both are displayed.

What range of dates can I convert?

JavaScript dates support roughly ±8.64 quadrillion milliseconds (about 275,000 years each way). Values outside that range are rejected because they cannot be represented as real dates.

Free Online Tool

Timestamp Converter

Convert Unix timestamps to readable dates and back instantly. Supports seconds and milliseconds with UTC and local time display.

Reviewed by Prime Metric • Updated September 2026 WhatsApp

Unix Timestamp → Date

UTCThu, 01 Jan 2026 00:00:00 GMT

Local1/1/2026, 12:00:00 AM

ISO 86012026-01-01T00:00:00.000Z

Date → Unix Timestamp

Seconds1767225600

Millis1767225600000

About this Tool

The Timestamp Converter translates between Unix time (seconds or milliseconds since January 1, 1970 UTC) and human-readable dates in both directions. Every timestamp is shown in UTC and your local timezone plus ISO 8601, so timezone mix-ups are easy to spot. All conversions run locally in your browser with no data sent anywhere.

Common Use Cases

Debugging APIs & Logs

Turn raw epoch values from API responses or server logs into readable dates to pinpoint exactly when an event happened.

Scheduling Cron Jobs

Convert a planned run time into a Unix timestamp for cron expressions, scheduled functions, or token expiry fields.

Fixing Timezone Bugs

Compare the UTC and local renderings side by side to confirm whether an off-by-hours bug comes from timezone handling.

Database Migration Checks

Verify migrated created_at values by spot-checking that stored integer timestamps map to the expected calendar dates.

Pro Tips

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Seconds vs Milliseconds
Modern JavaScript uses milliseconds (13 digits) while most backends and JWTs use seconds (10 digits). If your date lands in 1970 or year 50000, you picked the wrong unit.
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Trust UTC for Storage
Always store and exchange timestamps in UTC, converting to local time only for display. This avoids daylight-saving and timezone-offset bugs.
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Watch for Negative Values
Negative timestamps represent dates before 1970 and are valid. If you see one unexpectedly, check for uninitialized or default-zero date fields.

FAQs

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