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Developer guide

Unix Timestamp: Seconds vs Milliseconds

Tell apart 10-digit seconds and 13-digit milliseconds before converting a time.

Short answer

A Unix timestamp is commonly stored in seconds as a 10-digit value or milliseconds as a 13-digit value. Using the wrong unit produces a date that is dramatically wrong.

When this applies

Check documentation or a nearby known value when a timestamp is ambiguous. Some JavaScript APIs use milliseconds while many Unix-oriented APIs use seconds.

Practical review steps

  1. Count the digits, but treat that as a strong clue rather than the only evidence.
  2. Convert a known sample and compare it with the source event time.
  3. Keep the chosen unit explicit in API and database documentation.

Check the actual color pair

Use the free Time Shift with the foreground and background colors from the real component. It provides an immediate AA and AAA ratio check in the current browser tab.

Source and limit

For the formal requirement, review W3C's WCAG contrast minimum guidance. A ratio result checks a color pair; it is not a complete accessibility audit.