Unix Timestamp Converter
Convert Unix timestamps to readable dates and vice versa with timezone support.
Current Unix Timestamp
Convert Date to Unix Timestamp
Convert Unix Timestamp to Date
What Is a Unix Timestamp?
A Unix timestamp (also called Epoch time or POSIX time) is a way of tracking time as a running total of seconds. It counts the number of seconds that have elapsed since the Unix Epoch — January 1, 1970, at 00:00:00 UTC. This reference point was chosen by the creators of Unix because it was recent enough to keep numbers manageable, yet far enough back to be useful for most computing purposes.
The beauty of Unix timestamps is their simplicity: a single integer represents an exact moment in time, independent of time zones, daylight saving rules, and calendar quirks. The timestamp 1704067200 means January 1, 2024, 00:00:00 UTC no matter where in the world you read it. This makes timestamps the preferred format for storing, comparing, and transmitting time data in software systems.
The Year 2038 Problem (Y2K38)
Many older computer systems store Unix timestamps as a 32-bit signed integer, which has a maximum value of 2,147,483,647. This number corresponds to January 19, 2038, at 03:14:07 UTC. One second later, the integer overflows and wraps around to a large negative number, which would be interpreted as a date in December 1901.
This is the computing world's next "Y2K" — and it's more serious than the original because embedded systems (industrial controllers, IoT devices, car computers) are harder to update than desktop software. The fix is straightforward: use a 64-bit integer instead of 32-bit. Modern operating systems (Linux 5.6+, Windows, macOS) and programming languages already use 64-bit timestamps, which won't overflow for another 292 billion years.
Timestamp Formats Compared
| Format | Example | Used By | Precision |
|---|---|---|---|
| Unix (seconds) | 1704067200 | Linux, PHP, Python, C | 1 second |
| JavaScript (ms) | 1704067200000 | JavaScript, Java | 1 millisecond |
| Microseconds | 1704067200000000 | PostgreSQL, Go | 1 microsecond |
| ISO 8601 | 2024-01-01T00:00:00Z | JSON APIs, XML, databases | Variable |
| RFC 2822 | Mon, 01 Jan 2024 00:00:00 +0000 | Email headers, HTTP | 1 second |
| Windows FILETIME | 100-nanosecond intervals since 1601 | Windows OS, .NET | 100 nanoseconds |
Notable Timestamps
- 0 — January 1, 1970, 00:00:00 UTC (the Unix Epoch itself)
- 946,684,800 — January 1, 2000 (the Y2K moment)
- 1,000,000,000 — September 9, 2001 (the "billion seconds" milestone, celebrated by Unix enthusiasts)
- 1,234,567,890 — February 13, 2009, 23:31:30 UTC (the "1234567890 day" that nerds celebrated globally)
- 2,000,000,000 — May 18, 2033 (the next billion-second milestone)
- 2,147,483,647 — January 19, 2038 (the 32-bit overflow, a.k.a. Y2K38)
Getting Timestamps in Different Languages
| Language | Current Timestamp | Parse Date to Timestamp |
|---|---|---|
| JavaScript | Math.floor(Date.now() / 1000) | new Date('2024-01-01').getTime() / 1000 |
| Python | import time; int(time.time()) | datetime.strptime(...).timestamp() |
| PHP | time() | strtotime('2024-01-01') |
| Java | Instant.now().getEpochSecond() | LocalDate.parse(...).toEpochDay() * 86400 |
| Go | time.Now().Unix() | time.Parse(layout, value) |
| C / C++ | time(NULL) | mktime(&tm) |
Best Practices for Working with Timestamps
- Always store in UTC: Store timestamps in UTC and convert to local time only for display. This avoids ambiguity caused by time zone differences and daylight saving changes.
- Use ISO 8601 for APIs: When exchanging timestamps in JSON APIs, use ISO 8601 format (
2024-01-01T00:00:00Z) — it is human-readable, unambiguous, and supported by all JSON parsers. - Be aware of precision: JavaScript uses milliseconds, Python uses seconds (with decimal), and databases may use microseconds. Always check the precision when converting between systems.
- Handle time zones explicitly: Never assume a timestamp is in the local time zone. Always include the UTC offset or "Z" suffix in date strings to remove ambiguity.
- Test for edge cases: Daylight saving transitions, leap seconds, and the year 2038 problem can all cause subtle bugs. Test your time-handling code with dates near these boundaries.
Frequently Asked Questions — Unix Timestamp Converter
A Unix timestamp (also called epoch time) is the number of seconds elapsed since January 1, 1970, 00:00:00 UTC (the "Unix epoch"). It's a universal, timezone-independent way to represent a point in time as a single integer. For example, timestamp 1704067200 represents January 1, 2024, 00:00:00 UTC. Negative timestamps represent times before 1970.
On January 19, 2038, 32-bit signed integers used to store Unix timestamps will overflow (reaching the maximum value of 2,147,483,647). Systems using 32-bit time_t will wrap to a negative number, potentially causing date calculation errors. Modern 64-bit systems can store timestamps until the year 292,277,026,596 — effectively no limit. Most modern systems have already migrated to 64-bit timestamps.
Get current Unix timestamp: JavaScript: Math.floor(Date.now()/1000) or Date.now() for milliseconds. Python: import time; int(time.time()). PHP: time(). Java: System.currentTimeMillis()/1000L. Go: time.Now().Unix(). Bash: date +%s. SQL (MySQL): UNIX_TIMESTAMP(). Note: some systems use millisecond timestamps (JavaScript Date.now()) — divide by 1000 to get seconds.
Unix timestamps are traditionally in seconds. JavaScript's Date.now() and many modern APIs return milliseconds (13 digits). If you see a timestamp around 1,700,000,000 it's in seconds; around 1,700,000,000,000 it's in milliseconds. To convert: divide milliseconds by 1000 to get seconds. This distinction causes frequent bugs when mixing language ecosystems.
Use this tool to convert instantly. Programmatically: JavaScript: new Date(timestamp * 1000).toLocaleString(). Python: datetime.fromtimestamp(timestamp). PHP: date('Y-m-d H:i:s', $timestamp). Always specify a timezone — if omitted, the output uses the system's local timezone, which can differ between servers and cause hard-to-debug issues. Store as UTC, display in user's local timezone.