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Dates and time

Measure the time between two dates.

See calendar years, months, days, total elapsed days, complete weeks, and weekdays with the counting method explained.

Choose two dates

Why date answers can differ by one day

Elapsed time normally excludes the start date. From September 20 to September 21 is one elapsed day. Selecting the endpoint option counts both dates and makes that calendar count two days.

Calendar years and months are counted first because months have different lengths. Total days use date-only values, so daylight-saving changes do not add or remove an hour from the calculation.

For deadlines, contracts, court filings, travel, or benefits, use the counting rule specified by the responsible organization.