Time Calculator

Add / subtract / multiply / divide time, or find duration between dates and date-times.

⚙️ I want to

Switch the operation to change the input layout.

🎯 Units of result

Mixed “mo / y” modes use standard approximations; calendar modes below are exact.

Enter up to 20 values. A new row appears once you type in the last row.

For subtract, we compute: first row − (sum of the others).

⏱️ Time value

🧭 Unit

✴️ Factor

Multiply: time × factor ·· Divide: time ÷ factor.

📅 Start date

📅 End date

🕘 Start date & time

🕔 End date & time

Calculated precisely using your device’s locale support.

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