Calendar converter
Convert Gregorian, Persian and civil Islamic dates.
Open toolDate calculator
Find days between dates or add and subtract days.
Input & settings
Up to 1 MB · stays on this device
Result
Choose your settings and run the tool.
Readable text? Aa Bb 123
Foreground composited on your background
Foreground composited on your background
MonTueWedThuFriSatSun
How this tool works
Uses UTC dates so DST does not change a day count. Working days respect your selected weekend and up to 366 manually excluded Gregorian dates. Holiday data is not downloaded. Month/year offsets clamp to the last valid day: January 31 + one month becomes February 28 or 29.
Inputs and results stay in this page’s memory until you leave or reset it. Downloads remain on your device. Review the result before using it in another application.
Practical reading
Dates, durations and working days answer different questions
Avoid daylight-saving surprises and end-of-month mistakes in everyday date calculations.