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Date Tools

Unix Timestamp Converter

Convert Unix seconds and milliseconds to local time and UTC, or create timestamps from dates.

Choose values, then calculate.

Date-only calculations avoid timezone drift where practical. Business-day results do not include public holidays unless you explicitly add excluded dates in a future version.

How to use Unix Timestamp Converter

Set the values you need, press Start, and keep this browser tab open. Most tools store only practical preferences locally in your browser.

Timer accuracy is based on timestamps, so the display corrects itself after tab backgrounding. Browser alarms and notifications still depend on browser permission, power state, and open-tab behavior.