Date Difference Calculator

What this does. This calculator tells you exactly how many days sit between two calendar dates. By default it counts every day. Flip Weekdays only to count just Monday–Friday (business days). You can also choose whether the range is inclusive (start and end both counted) or exclusive (stop the day before the end). The result leads with the days so it’s instantly clear — then shows weeks+days, a real calendar breakdown (years–months–days), and a playful conversion into hours, minutes, and seconds.

Why it’s useful. Use calendar days for countdowns, reminders, anniversaries, and spans that don’t care about the workweek. Use business days for estimates, SLAs, staffing, and schedules that follow a Monday–Friday cadence. Keeping both perspectives visible avoids confusion: one number is for public dates and personal planning; the other tells you how many typical workdays fit inside the same window.

How to read it. The headline gives the main answer in bold. The subline repeats the exact date range and whether you chose inclusive or exclusive counting. A compact key–value list underneath compares calendar time and work time without mental math and includes a calendar-accurate years–months–days breakdown. If you typed the dates in reverse, the tool swaps them automatically and labels that fact so nothing looks suspicious later.

Edge cases handled. Leap years and month lengths are fully respected in the calendar breakdown; you won’t see “30 days per month” shortcuts. Because the tool works with whole local days, daylight-saving jumps don’t change the day totals. The inclusive switch prevents the classic off-by-one mistake when schedules say “through Friday” but someone counted exclusively.

Planning tips. Before you commit to a date range, run it both inclusive and exclusive to sanity-check your assumption. For team scheduling, record both calendar days and business days side by side — the first is great for countdowns and communications; the second guides staffing and throughput. For long projects, rely on the years–months–days line to summarize the span without losing accuracy across varying month lengths.

Holiday reference (U.S. federal). For convenience, here are upcoming federal holiday dates exactly as you provided them. The tables are optimized for phones: the date column never wraps and names wrap onto multiple lines instead of forcing sideways scroll.

Bottom line. You get a single, readable count in bold — backed by weeks, calendar breakdown, and a just-for-fun hours/minutes/seconds view. Keep the interface simple, and you’ll make faster, better date decisions.