- Are weekends counted?
- Yes. This page counts calendar days, which is what contracts mean when they say 90 days. If your deadline is written in working or business days, use the business days calculator instead: 90 working days is about four and a half months, not three.
- Is the start date itself counted?
- No. Day 1 is the day after the start date, the way notice periods and payment terms are normally read. If your case counts the start date as day 1, take one day off the result.
- Why 30, 60 and 90 days specifically?
- They are the spans commerce runs on: payment terms, probation periods, return windows, notice on a rolling contract. Nothing about them is astronomical, which is exactly why they are worth a calculator rather than a mental sum.
- Does it handle leap years and month lengths?
- Yes. The count runs on the real calendar, so a span crossing 29 February or a run of 31-day months comes out right without any adjustment.