Unix Timestamp Converter — Epoch to Date & Back
Convert Unix timestamps (seconds or milliseconds) to human dates and back — with relative time, ISO 8601, and your local timezone.
Last reviewed 2026-10-19. Rates change — verify against the official sources linked below before relying on these figures.
What this is based on
- Unit auto-detection: ≤10 digits = seconds, 11–13 = milliseconds, 14+ = microseconds.
- Relative times and 'now' are computed against your local clock at the moment you use the tool.
- Everything runs locally in your browser — pasted content is never uploaded, logged or stored.
Seconds vs milliseconds — the off-by-1000 bug
Unix time counts seconds since 1970-01-01 UTC. JavaScript's Date uses milliseconds — a factor of 1000 apart. Feed seconds into Date(ms) and your dates land in 1970+48 days; feed milliseconds into a seconds-expecting API and you get a date 50,000 years out. The 10-digit rule: current timestamps in seconds are 10 digits, in milliseconds 13 — this tool auto-detects on that boundary.
The 2038 problem (and why it mostly doesn't matter)
32-bit signed Unix time overflows on 2038-01-19 — the Y2K of embedded systems. Everything modern (databases, languages, OS kernels) uses 64-bit time, which lasts ~292 billion years. Where it still bites: legacy C code, embedded firmware, and old filesystem formats.
Frequently asked questions
- What is the current Unix timestamp?
- It's shown in the 'Now' result card — seconds since 1970-01-01 UTC. Today it's roughly 1.76 billion.
- How do I convert a timestamp to a date?
- Paste it above — seconds, milliseconds and microseconds are auto-detected. In code: JavaScript new Date(ms), Python datetime.fromtimestamp(s), SQL FROM_UNIXTIME(s).
- Why is my timestamp showing 1970?
- You fed milliseconds into a seconds-expecting function (or the reverse) — the classic off-by-1000. Check the digit count: 10 digits = seconds, 13 = milliseconds.
- Does Unix time include timezone?
- No — it's always UTC, a single global instant. Timezones are display-layer only, which is exactly why timestamps are the correct way to store times.
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