Timestamp converter · Guide
Timestamp Seconds vs Milliseconds
The single most common timestamp bug is mixing seconds and milliseconds. Telling them apart is easy once you count digits.
Count the digits
A current second-based timestamp has ten digits; a millisecond one has thirteen. If a value is a thousand times too big or small, you have the wrong unit.
Symptoms of a mismatch
Treating milliseconds as seconds throws dates thousands of years into the future; the reverse lands everything in 1970. A quick conversion reveals the mistake immediately.
Frequently asked questions
Can I use this for production work?
Yes, for inspection, formatting and quick generation. Still review the output before committing it to production code or configuration.
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