Unix Timestamp Converter
Convert between Unix timestamps and human-readable dates, in your local time zone.
Current Unix timestamp
—
UTC
Timestamp → Date
Date → Timestamp
What is it?
This tool converts between Unix timestamps (seconds or milliseconds since January 1, 1970 UTC) and human-readable dates in both your local time zone and UTC.
Formula Explanation
A Unix timestamp counts the number of seconds (or milliseconds) that have elapsed since the Unix epoch — midnight UTC on January 1, 1970. Converting to a readable date applies your browser's local time zone offset to that count; converting back subtracts the same offset before counting elapsed seconds from the epoch.
Example Calculation
The timestamp 1735689600 corresponds to January 1, 2025, 00:00:00 UTC.
How to Use
- To convert a timestamp to a date, paste it into the Timestamp field and choose seconds or milliseconds.
- To convert a date to a timestamp, pick a date and time in the Date field.
- Use "Use current time" to fill in right now's timestamp.
- Copy any result — local time, UTC, ISO 8601, seconds, or milliseconds.
Benefits
- Shows local time, UTC, and ISO 8601 all at once, so you don't need a separate time zone conversion step.
- Supports both seconds and milliseconds, the two most common timestamp formats used in APIs and databases.
- Displays a live-updating current timestamp for quick reference.
Use Cases
- Debugging an API response or database field that stores dates as Unix timestamps.
- Converting a log file timestamp into a readable local date and time.
- Getting the exact timestamp for scheduling a future event in code.
What Your Result Means
The Local time reflects your browser's detected time zone (shown above), while UTC and ISO 8601 are time-zone-independent — use UTC or ISO 8601 when sharing a timestamp with someone in a different time zone to avoid ambiguity.
Tips
- JavaScript's Date.now() and most JSON APIs use milliseconds, while many Unix/Linux tools and databases use seconds — double-check which one you need.
- ISO 8601 format (like 2025-01-01T00:00:00.000Z) is the least ambiguous way to store or share a timestamp across systems.
- If a timestamp looks 1000x too large or too small, you likely have the seconds/milliseconds unit swapped.
Common Mistakes
- Mixing up seconds and milliseconds, which produces a date far in the past or far in the future.
- Assuming a Unix timestamp already reflects a specific time zone — it's always a UTC-based count, and local time is only a display convenience.
- Forgetting that Unix timestamps are typically limited to dates after 1970 in most practical implementations.
FAQs
Does this tool send my timestamp or date data anywhere?
No, all conversion happens locally in your browser using standard JavaScript Date functions — nothing is sent to a server.
What time zone is 'Local' based on?
It's based on your browser's detected system time zone, shown above the current timestamp.
Why do seconds and milliseconds give different-looking numbers for the same moment?
A millisecond timestamp is exactly 1000 times larger than the equivalent seconds timestamp for the same instant.
Can this handle dates before 1970?
Yes, negative Unix timestamps represent dates before January 1, 1970, and this tool will convert them correctly.
All conversions happen locally in your browser using your system clock and time zone.
Last updated: July 27, 2026