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Unix Timestamp Converter

Convert Unix epoch timestamps to human-readable dates, or convert any date to a Unix timestamp. Live current time, UTC and local output, ISO 8601 format.

When developers reach for this

API responses and logs

Most APIs return timestamps as Unix integers (created_at: 1705312000). When debugging, you need the human date immediately — without doing mental math or leaving your editor.

Database queries

PostgreSQL, MySQL, and SQLite store timestamps as integers or epoch values in analytics tables. Converting to a date before writing a WHERE clause prevents off-by-one errors from timezone assumptions.

JWT expiry (exp claim)

JWTs store the expiry time as a Unix timestamp in the exp claim. Pasting that value here tells you exactly when the token expires — no math needed.

Log correlation

Server logs often use epoch timestamps for precision and compactness. Converting a log timestamp to a human date is the first step in correlating events across services.

Quick reference

Notable timestamps and what they represent

0
1970-01-01 00:00:00 UTC
Unix epoch — the origin
946684800
2000-01-01 00:00:00 UTC
Y2K
1000000000
2001-09-08 21:46:40 UTC
1 billion seconds
2147483647
2038-01-19 03:14:07 UTC
32-bit signed max (Y2K38)
1704067200
2024-01-01 00:00:00 UTC
Start of 2024
2000000000
2033-05-18 03:33:20 UTC
2 billion seconds

Frequently asked questions

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 00:00:00 UTC, not counting leap seconds. It's a single integer that unambiguously identifies any moment in time — no timezone or format ambiguity. Example: 1705312000 = January 15, 2024 at 10:26:40 UTC.

What's the difference between Unix time in seconds and milliseconds?

JavaScript's Date.now() returns milliseconds since epoch; most other languages and APIs return seconds. If your timestamp looks like 1705312000000 (13 digits), it's milliseconds — divide by 1000 to get seconds. If it's 10 digits, it's seconds. This tool accepts seconds.

Why do timestamps show a different time in UTC vs local?

Unix timestamps are timezone-agnostic — they represent a single absolute moment. The UTC output shows that moment in Coordinated Universal Time. The local output converts it to your browser's local timezone. If you're in UTC-5, a timestamp that's 10:00 UTC displays as 05:00 local. Neither is wrong; they're the same instant.

What is the Y2K38 problem?

Many systems store Unix timestamps as 32-bit signed integers. The maximum value a 32-bit signed int can hold is 2,147,483,647, which corresponds to January 19, 2038. After that date, such systems will overflow — either crashing or rolling back to 1901. Systems using 64-bit integers (most modern software) are safe until the year 292 billion.

What date formats does this tool accept for conversion to Unix?

The tool accepts any date string that JavaScript's Date constructor can parse: ISO 8601 (2024-01-15, 2024-01-15T10:30:00Z), common formats (January 15 2024, Jan 15, 2024), and datetime strings (2024-01-15 10:30:00). For best results, use ISO 8601 format with explicit timezone (Z for UTC).