How many days are between two dates?

Use NexLove's Date Calculator to enter your start and end dates; it computes total days, working days, weeks, and fractional months automatically.

How do I add 90 days to today's date?

Select the 'Add/Subtract' mode, enter today's date, input `+90` in the days field, and click calculate to see the exact future calendar date and day of the week.

Does the date calculator account for leap years?

Yes. All leap years (years divisible by 4, except centuries not divisible by 400) are fully accounted for in calendar date arithmetic.

How do you calculate business days between dates?

Business days count only Monday through Friday, automatically excluding weekend days (Saturday and Sunday) and optional public holidays.

Can I subtract months from a date?

Yes. Enter negative numbers or select 'Subtract' to calculate past dates accurately across month-end boundaries.

Can I add or subtract business working days excluding weekends?

Yes. You can choose whether to add pure calendar days or calculate deadlines based strictly on Monday–Friday business days.

Date & Time Cluster

Date Calculator (Days Between Dates & Add/Subtract Time)

Calculate duration between two dates, add/subtract calendar days, and count working days.

TL;DR: Date Calculator performs calendar arithmetic, finding the exact duration between two dates and calculating future or past dates by adding/subtracting days, weeks, or months.

Difference between dates

Add / subtract days

How Do You Calculate the Exact Number of Days Between Two Dates?

The number of days between two dates is calculated by converting both calendar dates into epoch timestamps (milliseconds since January 1, 1970 UTC), finding the absolute difference, and dividing by 86,400,000 (milliseconds in a day): Days = |Date 2 - Date 1| / (1000 × 60 × 60 × 24).

How to Use the Date Calculator

Our Date Calculator performs high-precision mathematical operations directly in your browser with zero latency and complete client-side privacy.

Select calculation mode: 'Days Between Two Dates' OR 'Add/Subtract Days from a Date'.
Enter Start Date and End Date (or starting date and days/weeks/months to add).
Optionally toggle 'Include End Date' in total day count.
Click 'Calculate Date' to view calendar intervals, weeks, months, and hours.
Review working business days (excluding Saturdays and Sundays).

Mathematical Formula & Equations

Calculates duration between two calendar dates in days, weeks, months, or adds/subtracts calendar days.

\[ \Delta t = \text{Date}_2 - \text{Date}_1, \quad \text{Future Date} = \text{Start Date} \pm N \text{ Days} \]

Calculation Example

Span between January 15, 2026 and November 26, 2026 is exactly 315 days (45 weeks).

100% Client-Side Privacy & Data Security

All calculations, amortization schedules, variables, and sensitive numerical datasets execute 100% locally in your web browser memory. Your financial, medical, and personal values are never transmitted, logged, or uploaded to any external server.

Frequently Asked Questions

: Use NexLove's Date Calculator to enter your start and end dates; it computes total days, working days, weeks, and fractional months automatically.
: Select the 'Add/Subtract' mode, enter today's date, input `+90` in the days field, and click calculate to see the exact future calendar date and day of the week.
: Yes. All leap years (years divisible by 4, except centuries not divisible by 400) are fully accounted for in calendar date arithmetic.
: Business days count only Monday through Friday, automatically excluding weekend days (Saturday and Sunday) and optional public holidays.
: Yes. Enter negative numbers or select 'Subtract' to calculate past dates accurately across month-end boundaries.
: Yes. You can choose whether to add pure calendar days or calculate deadlines based strictly on Monday–Friday business days.

Cite This Calculator

Need to reference this online calculator in a financial proposal, academic paper, blog post, or classroom curriculum? Copy a citation below.

NexLove.org. (2026). Date Calculator [Online Calculation Tool]. https://nexlove.org/tools/date-calculator

“Date Calculator.” NexLove.org, 2026, nexlove.org/tools/date-calculator.

NexLove.org (2026) Date Calculator. Available at: https://nexlove.org/tools/date-calculator (Accessed: 2026).

@misc{nexlove_date_calculator,
  title = {Date Calculator},
  author = {{NexLove.org}},
  year = {2026},
  url = {https://nexlove.org/tools/date-calculator}
}

Embed This Tool

Add the live Date Calculator to your own website with this snippet — it loads the real, working calculator in an iframe.

<iframe src="https://nexlove.org/embed/date-calculator.html" width="100%" height="600" style="border:1px solid #e2e8f0;border-radius:12px" title="Date Calculator — NexLove.org" loading="lazy"></iframe>

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