Date & Everyday
Date Difference Calculator
Calculate elapsed days and weeks between two dates.
How to use the date difference calculator
Calculate elapsed days and weeks between two dates. Enter the requested values and select Calculate result. Check the units and options before interpreting the answer.
Formula and calculation method
Elapsed days = later date − earlier date; the start date is excluded.
Worked example
1 January to 8 January is 7 elapsed days.
Limitations and interpretation
Results depend on inputs, assumptions and rounding. Verify results before using them for consequential decisions. Health estimates are not medical diagnoses.
Frequently asked questions
Are both dates included?
The result is elapsed days; inclusive counting adds one.
Can dates be reversed?
Yes, the interval is reported as an absolute difference.