UNIX Time Converter
Convert UNIX timestamps (seconds or milliseconds) to UTC/local time and back.
The tool auto-detects whether the input is 10-digit seconds or 13-digit milliseconds
and updates all fields in real time with no API calls.
View ISO 8601 output, human-readable strings, and the detected weekday.
Quick actions let you copy any field, jump to the current time, auto-refresh every second, or clear inputs.
All calculations are done in your browser using the native Date and Intl APIs.
Auto-detects seconds or milliseconds
Auto-syncs with UNIX input. Accepts local time.
Unix Timestamp Converter
Unix timestamps appear in logs, databases, API responses, JWT claims, analytics exports, and monitoring alerts. This converter turns second-based or millisecond-based timestamps into readable dates and helps you convert dates back into timestamp values.
Common use cases
- Debug logs: Convert raw timestamps into human-readable times during incident investigation.
- Check API fields: Review
created_at,updated_at,iat,exp, and expiration values. - Validate stored data: Confirm whether database timestamps match expected user actions or system events.
Seconds vs milliseconds
A 10-digit timestamp is often seconds, while a 13-digit timestamp is often milliseconds, but systems vary. If the resulting date looks far in the past or future, check whether you are using the correct unit.