Days between dates calculator: count days, weeks, weekdays, and months between any two calendar dates instantly. Free, runs in your browser, no signup.
Updates automatically as you type.
Calculated in your browser; your inputs are not sent to us. Privacy
Results will appear here.
Calculation details
Every figure above is calculated locally in your browser from the assumptions shown. No inputs are sent anywhere. See the methodology section below for the formulas used.
Use this resultShare the current inputs, or ask ChatGPT to explain the calculation in context.
Ask an AI to explain this result
Share this result
Planning estimate only, not financial, tax, or legal advice. Verify assumptions and current rules before making decisions.
This tool runs in your browser. Your calculator inputs and results are never transmitted to us or to ad/affiliate partners. Ads and sponsored links may set third-party cookies to serve and measure them, but they never receive your calculation values. If you explicitly save a scenario, its permitted fields stay in local browser storage until you clear them. See our Privacy Policy.
Use this result
Share the current inputs or ask ChatGPT to explain the calculation in context.
Days between dates calculator: count days, weeks, weekdays, and months between any two calendar dates instantly. Free, runs in your browser, no signup.
January 1 to March 1, 2026 spans 59 days and 42 weekdays.
Transparent methodology
How this calculator works
Reviewed August 2026 · BoringToolsKit Editorial Team
Formula
Days = end date − start date (exclusive); weeks = days ÷ 7; weekdays counts Mon–Fri only.
BoringToolsKit. “Days Between Dates Calculator.” boringtoolskit.com/days-between-dates-calculator/ (reviewed August 2026). Free to reference in articles, syllabi, and answer posts with a link.
Privacy: Inputs and results stay in this browser. Any future sponsored recommendation or advertisement will be clearly labeled and kept separate from the calculation.
Worked example: January 1 to March 1, 2026
Take a start date of January 1, 2026 and an end date of March 1, 2026. The calculator converts each date to midnight of its own day, subtracts, and divides by 86,400,000 milliseconds. January contributes 31 days and February 2026 contributes 28 (2026 is not a leap year), so the raw gap is 31 + 28 = 59 days. Dividing 59 by 7 gives 8.4 weeks, which the tool rounds to one decimal place as 8.4.
The weekday count is built by walking day by day. January 1, 2026 falls on a Thursday. The 59-day span contains 8 complete weeks (56 days) plus 3 leftover days: Thursday, Friday, Saturday. Eight weeks supply 8 x 5 = 40 weekdays, and the leftovers add 2 (Thursday and Friday), for 42 weekdays in total. A useful sanity check: March 1, 2026 lands on a Sunday, which matches 59 mod 7 = 3 days after a Thursday. Because the end date is excluded, counting March 1 itself would make it 60 days and 43 weekdays, so always read the result as the gap between the two dates, not an inclusive count.
Where the numbers can drift from reality
The engine treats a day as a fixed 86,400,000-millisecond block, which ignores daylight saving time. Crossing the US spring-forward date (March 8, 2026) or the fall-back date (November 1, 2026) means one calendar day is really 23 or 25 hours long. The rounded day count still comes out right, but if you multiply the day figure by 24 to bill hours, a 59-day span crossing March 8 actually contains 1,415 hours, not the 1,416 the flat multiplication implies.
Weekdays is a raw count, not a business-day total. It never subtracts holidays: the 42 weekdays in the January 1 to March 1 example would drop to 38 for a US employer observing New Year's Day and Presidents' Day, and to 39 for one observing only New Year's Day. Leap years shift things too: the same January 1 to March 1 window in 2028 spans 60 days because February has 29, and weekday counts restart from whatever day of the week the start date lands on. For contract or payroll deadlines, verify the inclusive/exclusive convention in writing, since legal counting rules vary by jurisdiction.
