Skip to content

Timestamp Converter

Convert timestamps and dates while making seconds vs milliseconds mistakes obvious before they break auth, sorting, or scheduled work.

Timestamp → Date
Example: 1711022400 or 1711022400000
Date → Timestamp
ISO example: 2026-03-21T12:00:00Z
ISO (UTC)
Local
Seconds
Milliseconds

Why this tool matters more than it looks

Timestamp bugs are small, silent, and expensive. A value can look plausible and still be completely wrong for the system reading it.

Auth and token expiry

JWT exp, iat, and nbf are usually in seconds. Reading them as milliseconds creates fake expiry bugs and wrong trust decisions.

Sorting and analytics

A timestamp in the wrong unit can reorder records, distort charts, or make recent events look ancient.

Scheduled jobs and cron

When cron, queues, or delayed jobs depend on timestamps, unit mistakes create incidents that look like scheduler failures.

What usually goes wrong

The problem is rarely the date itself. It is usually the assumption behind how the date was stored, parsed, or displayed.

Seconds vs milliseconds

10 digits usually mean seconds. 13 digits usually mean milliseconds. Mixing them often sends dates to 1970 or absurd future years.

UTC vs local time

A timestamp can be correct in UTC and still look wrong in the UI because the reader expected local time, or the opposite.

String parsing assumptions

A date string without timezone information may be interpreted differently by backend services, browsers, or languages.

What this tool will not validate for you

Converting a timestamp is only one part of the story. You still need to validate the surrounding contract and business meaning.

Business semantics

The converted date may be correct, but the event may still be wrong for your domain: wrong timezone policy, wrong cutoff, wrong retention rule.

Source of truth

If multiple services transform the same timestamp, you still need to find where the wrong unit or timezone was introduced.

Operational impact

This page helps you inspect the value. It does not guarantee that queues, schedulers, or auth middleware are using it consistently.

Related tools and reading

Use these when the timestamp value is only one piece of a larger auth, scheduling, or debugging problem.