Date Calculator
Add or subtract days from a date, or count days between dates.
90 days after
January 20, 2027
Day of week
Wednesday
Deadlines and windows
Contract deadlines, return windows, and medication schedules all reduce to date arithmetic. '90 days from signing' counts calendar days by default — business-day counts differ, and this matters exactly when a deadline lands on a weekend.
Inclusive or exclusive?
'Days between' here excludes the start day and includes the end (June 1 → June 3 = 2 days). Legal and billing contexts sometimes count inclusively — one day more. When a deadline matters, confirm which convention applies.
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