Lead Time Calculator
A supplier quotes “10 business days” — but which date is that, exactly? Enter the order date and the lead time, choose calendar or business days, and get the expected delivery date with the true calendar span shown.
Results
Formula
How to use this calculator
- Enter the order (or start) date.
- Enter the quoted lead time in days.
- Choose business or calendar days to match the quote, then Calculate.
Worked example
Ordered Friday, November 6, 2026, with a 5-business-day lead time.
- Count: Mon 9 (1), Tue 10 (2), Wed 11 (3), Thu 12 (4), Fri 13 (5).
Result: Expected delivery: Friday, November 13, 2026 — a 7-calendar-day span.
Frequently asked questions
Why does the count start the day after ordering?
That is the standard commercial convention: the order day is day zero. Some suppliers count the order day itself — if a quote matters, confirm the convention with the supplier.
Are holidays excluded in business-day mode?
No — only weekends. Supplier holidays and shutdowns (common around year-end) can push real deliveries later.
Lead time vs delivery time — same thing?
Lead time is the full span from order to delivery, including processing and production. Shipping/transit time is only the final leg of it.
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