Calculate the difference between two calendar dates.
The result includes absolute days, weeks, approximate months, approximate years, and whether the end date is before, after, or on the same day as the start date.
The calculation compares date-only UTC values to avoid local daylight-saving offsets changing the day count.
When to use it
Plan project milestones, compare contract start and end dates, or explain approximate month and year spans alongside exact day counts for reporting dashboards.
Limitations
Results depend on the values you enter and standard browser math; they are not audited for regulatory compliance. Very large inputs, locale-specific rounding, or edge cases may differ from spreadsheet or server implementations.
Example
For example, enter the default sample values on the form and compare the output with a known reference; adjust one input at a time to see how the result changes.