Timestamp Converter
Convert Unix timestamps to human-readable dates and vice versa.
Timestamp Converter — Unix Timestamp to Date & Back
Convert Unix timestamps to human-readable dates and vice versa with our free online Timestamp Converter. Supports seconds, milliseconds, ISO 8601, UTC, local time, and relative time — all processed locally in your browser.
What Is a Unix Timestamp?
A Unix timestamp (also called epoch time or POSIX time) is the number of seconds that have elapsed since January 1, 1970 (UTC), excluding leap seconds. It is the most common way computers represent dates and times internally. Because it is a single integer, it is easy to store, compare, and calculate with.
For example, the Unix timestamp 1700000000 corresponds to November 14, 2023, 22:13:20 UTC. Timestamps in milliseconds (like JavaScript's Date.now()) are the same concept multiplied by 1,000 — so 1700000000000 is the same moment.
Unix timestamps are used everywhere: databases, APIs, log files, cron jobs, file systems, and programming languages. Converting between timestamps and human-readable dates is one of the most common tasks in software development.
How to Use This Timestamp Converter
Using the tool is straightforward:
- Enter a Unix timestamp in the left card. The converter auto-detects whether your input is in seconds or milliseconds — use the toggle button to switch.
- Or pick a date and time in the right card using the date-time picker. The timestamp updates automatically.
- Click "Now" to jump to the current moment and get its timestamp instantly.
- View the results below — local time, UTC, ISO 8601, relative time, day of week, week number, and day of year are all displayed with copy buttons.
Key Features
| Feature | Benefit |
|---|---|
| Bidirectional Conversion | Enter a timestamp to get a date, or enter a date to get a timestamp |
| Seconds & Milliseconds | Toggle between seconds (Unix) and milliseconds (JavaScript) |
| Live Current Timestamp | See the current Unix timestamp ticking in real time |
| ISO 8601 Output | Get the standard ISO date format for APIs and databases |
| Relative Time | See how far the timestamp is from now (e.g., "3h ago") |
| Day of Week & Year | Get extra calendar info — day name, week number, day of year |
| One-Click Copy | Copy any result value to clipboard instantly |
| Browser-Only | No data sent to any server — your timestamps stay private |
Common Use Cases
Debugging API Responses
REST APIs often return dates as Unix timestamps or ISO 8601 strings. Paste the timestamp into this tool to quickly see the human-readable date. If you need to inspect JWT tokens that contain timestamps, try our JWT Decoder.
Working with Cron Jobs
When configuring cron expressions, you often need to verify what time a specific timestamp corresponds to. Paste the timestamp here and confirm. You can also use our Cron Expression Parser to build and validate cron schedules.
Log File Analysis
Server logs frequently use Unix timestamps. Convert them to readable dates to understand when events occurred. For comparing two log entries side by side, try our Diff Checker.
JavaScript Development
JavaScript's Date.now() returns milliseconds. Use this converter to switch between seconds and milliseconds, or to verify that your date calculations are correct.
Tips for Working with Timestamps
- Watch the unit. Unix timestamps are typically in seconds (10 digits), while JavaScript uses milliseconds (13 digits). Mixing them up gives you a date in 1970 or far in the future.
- Time zones matter. The same Unix timestamp represents a different local time depending on the timezone. This tool shows both your local time and UTC.
- ISO 8601 is the safest format. When exchanging dates between systems, ISO 8601 (
2024-01-15T10:30:00.000Z) avoids ambiguity. - Use "Now" as a starting point. Click the "Now" button to get the current timestamp, then adjust the date picker to find the timestamp for a future or past date.
Frequently Asked Questions
Is this Timestamp Converter free?
Yes. It is completely free, requires no account, and has no usage limits. All conversion happens in your browser.
What is the difference between seconds and milliseconds?
Unix timestamps are traditionally in seconds (10 digits for recent dates). JavaScript and some other systems use milliseconds (13 digits). The tool supports both — use the toggle button to switch.
Does the tool handle dates before 1970?
Yes. Negative Unix timestamps represent dates before January 1, 1970 UTC. Enter a negative number to convert dates in the 1960s or earlier.
Is my data sent to a server?
No. All conversions are performed locally in your browser. No timestamps or dates are transmitted anywhere.
What formats does the results section show?
The results show local time, UTC time, ISO 8601, relative time (e.g., "2h ago"), Unix seconds, Unix milliseconds, day of the week, ISO week number, and day of the year.