Unix Timestamp Converter - How to Convert Between Timestamps and Dates

Unix timestamps are everywhere - APIs, databases, logs, and configuration files. But reading 1749254400 and knowing it is a specific date is not something humans do well. A timestamp converter bridges the gap between machine and human time.

What Is a Unix Timestamp?

A Unix timestamp (also called Epoch time or POSIX time) is the number of seconds elapsed since January 1, 1970, 00:00:00 UTC - not counting leap seconds. It is the universal standard for representing time in computing.

• Seconds: 10 digits (e.g., 1749254400) - standard in most APIs and databases
• Milliseconds: 13 digits (e.g., 1749254400000) - used in JavaScript, Java, and some databases
• Microseconds: 16 digits - used in high-precision applications

Common Timestamp Formats

• Unix timestamp: 1749254400
• ISO 8601: 2025-06-07T00:00:00Z
• RFC 2822: Sat, 07 Jun 2025 00:00:00 +0000
• HTTP date: Sat, 07 Jun 2025 00:00:00 GMT

Free Online Timestamp Converter

Use SnapSum Timestamp Converter to convert between Unix timestamps and human-readable dates - instantly, in your browser.

• Timestamp to date/time (seconds and milliseconds)
• Date/time to timestamp
• Current timestamp displayed live
• Multiple output formats (ISO 8601, UTC, local time)
• Relative time display ("2 hours ago", "in 3 days")

Step-by-Step: Convert a Timestamp

1. Open Timestamp Converter.
2. Paste a Unix timestamp or pick a date/time.
3. See the converted result instantly in all formats.
4. Copy the format you need.

Timestamp Gotchas

• Seconds vs. milliseconds - JavaScript uses milliseconds (13 digits), most APIs use seconds (10 digits). Mixing them up gives dates in 1970 or 53677.
• Time zones - timestamps are always UTC. When displaying to users, convert to their local timezone.
• 2038 problem - 32-bit signed integers overflow on January 19, 2038 (2,147,483,647). Modern systems use 64-bit, but legacy code may break.
• Leap seconds - Unix time does not count them, so two timestamps can be 1 second apart but represent the same real-time instant.

Quick Reference

• 0 = January 1, 1970, 00:00:00 UTC
• 1000000000 = September 9, 2001
• 1500000000 = July 14, 2017
• 2000000000 = May 18, 2033

For related time tools, see Cron Parser for scheduling and Unit Converter for time unit conversions.