Overview
Enter a Unix timestamp - in seconds or milliseconds, auto-detected by digit count so "1735689600" and "1735689600000" both resolve to the correct moment - or a date string like an ISO 8601 timestamp, and see it converted into every format you’d actually need at once: Unix seconds, Unix milliseconds, ISO 8601, a UTC string, your browser’s local time string, and a relative description like "3 days ago" or "in 2 hours". This eliminates the usual back-and-forth of converting a timestamp, realizing it’s off by a factor of 1000, and converting again - the digit-count heuristic (13+ digits means milliseconds, fewer means seconds) handles that automatically. A "Now" button fills in the current timestamp instantly for quick reference. Runs entirely client-side using your browser’s own timezone.
Best for: Making sense of a Unix timestamp in a log file
How to use this tool
- Paste a timestamp or date. A Unix timestamp (seconds or milliseconds) or a date string like an ISO 8601 value.
- The format is auto-detected. Digit count determines whether a numeric input is seconds or milliseconds - no unit to pick manually.
- See every format at once. Unix seconds, Unix milliseconds, ISO 8601, UTC, local time, and a relative description all appear together.
- Use "Now" for the current time. Fill in the current timestamp instantly for quick reference or comparison.
Why use this tool
Auto-detects seconds vs. milliseconds
No more guessing why a timestamp looks 1000x too large or small - digit count handles it automatically.
Six formats at once
Unix, ISO 8601, UTC, local time, and relative time all shown together instead of one at a time.
Relative time included
See "3 days ago" or "in 2 hours" alongside the raw values, not just numbers to mentally convert.
One-click current time
The "Now" button fills in the current timestamp instantly for quick comparisons.
Frequently asked questions
It counts the digits: a Unix timestamp in seconds for a modern date has 10 digits, while the same moment in milliseconds has 13. The converter treats 13+ digit numbers as milliseconds and shorter numbers as seconds, which correctly handles the vast majority of real-world timestamps without you needing to specify the unit manually.
A single point in time corresponds to different clock readings depending on timezone - the UTC string always shows the moment in Coordinated Universal Time, while the Local string reflects your browser’s configured system timezone. Both describe the exact same instant; only the displayed clock time and offset differ.