Date Calculator

Add Days to a Date

Add business days or calendar days to any start date. Automatically excludes weekends and public holidays.

Common Additions From Today

Popular Day Additions

Add 90 Days to a Date

90 days is commonly used for probation periods, insurance claims, warranty periods, and government processing deadlines. 90 calendar days is about 3 months. 90 business days is about 4.5 months (roughly 18 weeks).

Add 30 Days to a Date

30 days appears in payment terms (Net 30), benefits enrollment windows, cancellation notice periods, and return policies. 30 business days is about 6 calendar weeks.

Add 60 Days to a Date

60 days is used for SEC filing deadlines, employee review periods, escrow timelines, and COBRA enrollment windows. 60 business days is about 12 calendar weeks.

Add 45 Days to a Date

45 days is common in mortgage processing, 1031 exchange identification periods, and insurance claim resolutions. 45 business days is about 9 calendar weeks.

Add 120 Days to a Date

120 days appears in patent filing deadlines, FDA review periods, and long-term project milestones. 120 business days is about 24 calendar weeks (nearly 6 months).

Business Days vs Calendar Days

The difference matters more than most people realize:

Days AddedCalendar Days ResultBusiness Days Result
3030 days (~4 weeks)42 days (~6 weeks)
6060 days (~8.5 weeks)84 days (~12 weeks)
9090 days (~13 weeks)126 days (~18 weeks)
120120 days (~17 weeks)168 days (~24 weeks)

Business day counts stretch even further when public holidays fall within the period. A 90-business-day deadline set in November could extend past the following April due to Thanksgiving, Christmas, New Year's, and MLK Day.

How does this calculator work?

Enter a start date, choose the number of days to add, and select whether you want business days (excludes weekends and holidays) or calendar days (counts every day). The calculator skips weekends (Saturday and Sunday) and public holidays for your selected country when counting business days.

Does Day 1 start on the start date or the day after?

The count starts on the day after the start date. If you enter June 1 and add 1 business day, the result is June 2 (assuming it's a weekday and not a holiday). This matches how most legal and business contracts count days.

Which holidays are excluded?

The calculator uses the major public/federal holidays for the selected country. For the US, this includes New Year's Day, MLK Day, Presidents' Day, Memorial Day, Juneteenth, Independence Day, Labor Day, Columbus Day, Veterans Day, Thanksgiving, and Christmas. Other countries use their respective national holidays.

More Calculators

Business Days Calculator
Count working days between dates
Days From Today
Find a date X business days from now
Is Today a Business Day?
Instant daily check
Business Days FAQ
18 common questions answered
Working Days in a Year
Compare by country
Business Days Until
Countdown to any date

Get Monthly Business Day Alerts

We'll send you next month's business day count and upcoming holidays — one email, no spam.