Unix Timestamp Guide for Reliable Incident Timelines

Timestamp confusion causes real outages. This guide helps you distinguish seconds vs milliseconds, UTC vs local display, and safe conversion patterns.

Seconds vs milliseconds

A 10-digit Unix value is usually seconds. A 13-digit value is usually milliseconds. Treating one as the other shifts dates by decades and breaks event correlation.

Store UTC, display local

Persist timestamps in UTC for consistency, then convert to local time only for UI display. Timestamp Converter helps compare both representations.

Parsing date strings safely

  • Prefer ISO 8601 with timezone offsets.
  • Avoid locale-dependent date formats in APIs.
  • Keep logs explicit about timezone context.

Operations checklist

  • Normalize event timestamps before sorting.
  • Annotate dashboards with timezone assumptions.
  • Use one conversion source of truth in postmortems.