Unix timestamps use different units depending on the language and system. The most common are seconds and milliseconds.
- Seconds — Unix systems, PHP
time(), most APIs. The current time is a 10-digit integer. - Milliseconds — JavaScript
Date.now(), JavaSystem.currentTimeMillis(). The current time is 13 digits. - Microseconds — some high-precision logs and databases. Around 16 digits.
Confusing the unit throws the time off by a factor of 1,000, landing you in 1970 or the far future. AG TIME auto-detects the unit from the digit count, and when it's ambiguous you can set the unit yourself in the converter.