What is Unix Timestamp Converter
The Unix Timestamp Converter translates between Unix epoch timestamps and human-readable date/time formats. A Unix timestamp is the number of seconds (or milliseconds) that have elapsed since midnight on January 1, 1970 UTC — the Unix epoch. This tool accepts three types of input: a numeric Unix timestamp (in either seconds or milliseconds, controlled by the Units selector), a human-readable date string (e.g., "2024-03-15" or "March 15, 2024"), or an empty input (which defaults to the current moment). The output displays the date in multiple formats simultaneously: ISO 8601 (2024-03-15T14:30:00.000Z), UTC string (Fri, 15 Mar 2024 14:30:00 GMT), the browser's local time representation, the Unix timestamp in seconds, the Unix timestamp in milliseconds, and a relative time string (e.g., "3 hours ago" or "in 2 days"). This multi-format output makes it a universal converter for any timestamp format you encounter in logs, databases, APIs, or configuration files.
How to Use Unix Timestamp Converter
- Step 1: Open the tool and set the Units toggle in the options bar: choose Seconds (default) if your timestamp is in seconds, or Milliseconds if it is in milliseconds. This matters because JavaScript timestamps are in milliseconds, while most databases and APIs use seconds.
- Step 2: Paste a Unix timestamp (e.g., 1710512400), a date string (e.g., 2024-03-15T14:30:00Z or March 15 2024), or leave the input empty to use the current moment.
- Step 3: Click Transform. The output panel displays the date in all six formats, with the Unix timestamps in both seconds and milliseconds, so you can copy whichever format you need.
- Step 4: To convert in the other direction (human-readable to Unix), paste a date string and read the Unix (s) or Unix (ms) line from the output.
Why Use Unix Timestamp Converter
Unix timestamps appear everywhere in software: database columns, JWT exp claims, API query parameters, git commit dates, log timestamps, and cookie expiry values. Converting between human-readable dates and Unix timestamps is a constant need during development, debugging, and data migration. The converter eliminates the mental math and timezone confusion that often accompanies manual conversion. The multi-format output is especially valuable when you encounter a timestamp in an unfamiliar format and need to understand what it represents — pasting it into this tool immediately shows you the human-readable date in multiple conventions, the relative time, and equivalent timestamps in both units.
Privacy & Security
This tool runs entirely in your browser — no data ever leaves your device. There is no server round-trip, no upload, no logging, and no account required. Your input is processed locally using client-side JavaScript and is never stored, transmitted, or accessible to anyone else. When you close the tab, everything disappears.
Frequently Asked Questions
What is the difference between seconds and milliseconds?
<p>Unix timestamps in seconds are 10-digit numbers (e.g., 1710512400). Millisecond timestamps are 13-digit numbers (e.g., 1710512400000). JavaScript's Date.getTime() returns milliseconds, while most databases, APIs, and Unix tools use seconds. Toggle the Units selector to match your input format.</p>
Can I convert a future date?
<p>Yes. Paste any future date string or timestamp and the tool will display it with a relative time like "in 5 days" or "in 3 months". This is useful for setting token expirations, scheduling, and planning.</p>
What date formats does the input accept?
<p>The tool uses JavaScript's Date constructor, which accepts ISO 8601 strings (2024-03-15), RFC 2822 strings, and many other formats. It may not accept ambiguous formats like 03/15/2024 (US) vs 15/03/2024 (EU) — use ISO format for clarity.</p>