Guides. Unix Time & Timestamps, Explained
In-depth, hands-on articles about Unix time and the timestamp formats developers actually meet. Each one is written by the Real Epoch Converter team, reviewed against the underlying specifications, and linked to a tool that does the conversion for you.
A timestamp is just a number, but the number only makes sense once you know the clock it counts, the unit it uses, and the epoch it starts from. These guides cover exactly that — the concepts in plain language, the gotchas that cost real incidents, and the few numbers worth memorizing.
What Is Unix Time? The Epoch Explained for Developers
A clear, from-first-principles look at Unix time: what the epoch is, how seconds are counted, why 1970, and the 2038 boundary.
How to Read Unix Timestamps in Logs, Fast
Server logs, databases, and APIs are full of 10- and 13-digit numbers. Learn the mental shortcuts that turn them into dates in seconds.
Seconds, Milliseconds, or Microseconds? Detecting a Timestamp’s Unit
The most common timestamp bug is mixing up units. This guide shows you how to identify seconds, milliseconds, and microseconds from the digits alone.
ISO 8601 vs Unix Time: When to Use Which
Both formats record an instant, but they fail in opposite ways. A practical comparison for APIs, databases, and log pipelines.
Leap Seconds and GPS Time: Why Two Clocks Disagree
UTC inserts leap seconds, GPS time ignores them, and Unix time pretends they never happen. Here is what each clock is actually counting.
Snowflake IDs: The Timestamps Hidden in Discord and Twitter IDs
Discord, Twitter/X, and many internal systems ship 64-bit IDs with a timestamp built in. Learn to read the bits and decode them by hand.
Windows Time Formats: FILETIME, .NET Ticks, and the 1601 Epoch
FILETIME, LDAP timestamps, WebKit times, and .NET ticks all descend from the same 100-nanosecond idea. This guide untangles the family tree.
7 Timestamp Bugs That Bite Every Developer
A field guide to the timestamp mistakes that cost real incidents — unit mix-ups, timezone slips, precision loss, and more — with fixes.
New to Unix time?
Start with What Is Unix Time? if you want the foundation, or jump straight to the online epoch converter if you have a number in front of you right now. Every converter on this site works entirely in your browser, and the methodology page documents exactly how each edge case is handled.