Date & Time

Calculate date differences, add or subtract dates, and convert timestamps and time zones.

Runs locally in your browser

This tool does not upload your input to Khmind servers. Sensitive content should still be handled carefully on shared devices.

Date difference

Start dateEnd date

Elapsed calendar days; the starting day is not counted.

Add or subtract dates

Base date

Amount (negative to subtract)Unit

Month/year arithmetic clamps to the last valid day, for example January 31 + 1 month.

Timestamps & time zones

Conversion

Unix timestampTimestamp unit

Display time zone

Use an IANA time zone such as Asia/Phnom_Penh, Asia/Shanghai, America/New_York, or UTC. Ambiguous or nonexistent daylight-saving local times are rejected.