Quickly find the number of days between two dates — with options for calendar breakdowns, business days, and JSON output.
What it does
Calculates the difference between two dates. Choose plain days, calendar breakdown (years/months/days), business days (excludes weekends), and copy results as formatted text or JSON.
Key Features
- Days between two dates (inclusive or exclusive)
- Calendar breakdown: years, months, days
- Business days (Mon–Fri) count option
- Output as readable text or structured JSON
- Robust validation and friendly error messages
Tip: Leave date inputs empty and paste two dates into the textarea (e.g. 2025-01-15 to 2025-02-20) — then click Calculate.
How to use (step-by-step)
- Pick a start and end date (or paste two dates in the textarea).
- Choose whether to include the end date and/or count business days only.
- Select output mode: Text or JSON.
- Press Calculate. Results appear in the textarea.
- Use Copy to copy output, or Clear to reset.
Real-World Use Cases
- Project timelines — find days between milestones.
- Leave/vacation calculations for HR.
- Billing/proration and subscription date calculations.
- Event planning and countdowns.
Benefits
- Fast, reliable date math — avoids timezone pitfalls.
- Clear, exportable output (text or JSON).
- Mobile-friendly UI for quick on-the-go checks.
FAQ
How is a “day” defined?
A day here is a calendar day difference computed using UTC-midnight arithmetic to avoid timezone shifts affecting the count.
Can I include the end date?
Yes — toggle Include end date. When checked, the end date is counted as part of the interval.
What formats are accepted when pasting dates?
ISO (YYYY-MM-DD) is preferred. The tool also accepts common formats like DD/MM/YYYY and MM/DD/YYYY if unambiguous. If ambiguous, prefer ISO.
How are business days calculated?
When Business days is selected the calculator excludes Saturdays and Sundays. Public holidays are not considered.
Can I get the output as JSON?
Yes — choose the JSON output mode. The JSON includes start, end, days, businessDays (if requested) and breakdown when available.