Date Calculator
Calculate the absolute calendar-day difference between two dates and add or subtract whole days from the starting date.
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Date Calculator
Calculate the absolute calendar-day difference between two dates and add or subtract whole days from the starting date.
Both results are produced together. January 1 to January 3 is 2 elapsed calendar days, not an inclusive count of 3 dates. Reversing the dates keeps the difference nonnegative. The adjustment must be an integer from −1,000,000 to 1,000,000; this is calendar arithmetic, not a count of 24-hour periods.
2026-01-01 → 2026-01-03: 2 2026-01-01 + 2 = 2026-01-03
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