Days Between Dates Calculator
Select a start date and an end date to instantly calculate the total days between them — plus weeks, business days, weekend days, hours, and minutes. No signup, runs entirely in your browser.
Select both dates above to see results.
How to Use the Days Between Dates Calculator
- 1Set your Start date using the date picker — it defaults to 30 days before today.
- 2Set your End date — it defaults to today. You can type dates directly or use the calendar popup.
- 3The total days between the dates appears instantly in the result card, alongside weeks, business days, weekend days, hours, and minutes.
- 4Use the ⇄ swap button to reverse the dates, or Reset to today to return to the default range.
When You Need to Count Days Between Dates
Date difference calculations arise in almost every area of life and business. Project managers calculate the number of working days between a kick-off and a deadline. HR teams work out notice periods and probation lengths. Landlords and tenants calculate rental periods. Finance teams count days between invoice date and payment due date. Travellers count days until a trip or verify how long a visa allows them to stay.
The business days breakdown is particularly useful in professional contexts. A deadline that is "15 days away" feels different when you know only 10 of those are working days — and the days available for actual work may be fewer still if you account for meetings, reviews, and dependencies.
Common Uses for Days Between Dates
Project Deadlines
Calculate working days between today and a deadline to know how much real production time you have. A 20-day window contains only 14–16 working days once weekends are removed.
Contract and Notice Periods
Employment contracts, lease agreements, and service contracts often specify notice periods in calendar days. Count exactly to ensure you comply with the required notice window.
Invoice Payment Terms
Net 30, Net 60, and Net 90 payment terms are in calendar days from the invoice date. Calculate the exact payment due date and the days remaining before it falls overdue.
Visa and Travel Duration
Many visa categories limit stays by calendar days. Count your intended stay precisely to stay within the allowance — overstaying even by one day can affect future visa applications.
Pregnancy and Medical Timelines
Count days between medical appointments, calculate gestational age in days from a reference date, or track the duration of a treatment or recovery period precisely.
Event Planning
Count down days to a wedding, conference, product launch, or important date. Knowing exactly how many days — and how many working days — remain changes how you plan your preparation.
Frequently Asked Questions
How does the days between dates calculator work?
Enter a start date and an end date. The calculator finds the absolute difference in calendar days between the two dates — it does not matter which date is earlier. The result is shown in total days, complete weeks (plus remaining days), approximate months, business days (Monday to Friday), weekend days, total hours, and total minutes.
How are business days counted?
Business days are counted by iterating through every day between the start and end dates (inclusive of both) and counting only days that fall on Monday, Tuesday, Wednesday, Thursday, or Friday. Public holidays are not excluded — the calculator counts working weekdays only, not market or regional holidays, which vary by country.
Does the calculator include both the start and end date?
Yes. Both the start date and end date are included in the count. If you select 1 May and 3 May, the result is 2 days (the difference between the dates), not 3. If you want to include both endpoints (e.g. for a rental period where day one and day last are both full days), add 1 to the result.
How accurate is the "approximate months" figure?
The months figure uses an average month length of 30.4375 days (365.25 ÷ 12), which accounts for leap years. Because calendar months vary between 28 and 31 days, this is an approximation — "2 months + 3 days" means roughly two average months and three days. For exact calendar month differences, use the age calculator.
What does the swap button do?
The swap button exchanges the start and end dates. This is useful when you want to reverse the direction of the calculation — for example, switching from "days until a deadline" to "days since a start date" without retyping.
Can I calculate days between historical or future dates?
Yes — the date inputs accept any valid calendar date. You can calculate the number of days between events centuries apart or plan timelines far into the future. All calculations run in your browser using JavaScript's Date object.
Is my data stored or sent anywhere?
No. The calculator runs entirely in your browser. No dates, results, or personal information are transmitted to any server or stored anywhere. Refreshing the page resets the inputs.