← Utilities

Unix Timestamp Converter

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Convert a Unix timestamp to ISO/UTC/local time, or a date string back to a timestamp — seconds vs milliseconds auto-detected.

How it works

  • Unix timestamp → date: paste a number and it’s shown as ISO 8601, UTC, your browser’s local time, and a relative phrase (“2 hours ago”). Whether you meant seconds or milliseconds since the epoch is auto-detected by digit count — 10 digits or fewer is seconds (valid through the year 2286), 11–13 digits is milliseconds.
  • Date → Unix timestamp: paste any string JavaScript’s Date constructor understands — ISO 8601 (2025-01-15T10:30:00Z) is the most reliable format across browsers; a date-only string like 2025-01-15 is interpreted as UTC midnight.
  • Click any value in the results to copy it.

Runs entirely in your browser using its built-in Date and Intl.RelativeTimeFormat APIs — nothing you enter is uploaded, logged, or stored.

🔑 Also try: JWT Decoder → ·its exp/iat claims are Unix seconds 🧮 Also try: Number Base Converter →