Calculate a delivery date or an order-by date using lead time in weeks or days. Choose calendar days or business days (weekends excluded).
Date-based lead time is the simplest and most common planning method. You add or subtract a known lead time to find the date you need.
Use this when you know the start date (order date, kickoff date, request date) and you want to know when the output will be ready (delivery, completion, arrival).
Use this when you know the date you must have something by and you want the latest date you can start or place the order.
Lead time shows up everywhere... especially when dates and commitments matter.
Calendar days count every day. Business days exclude weekends. If your lead time depends on holidays, adjust the result date or use a dedicated holiday calendar.
Start date: March 1. Lead time: 14 days. Output: Delivery date is March 15 (calendar days).
Need-by date: April 30. Lead time: 3 weeks. Output: Order-by date is three weeks earlier (calendar weeks).
Start date: Monday. Lead time: 5 business days. Output: Delivery date is the following Monday (weekends excluded).
Tip: If you want a buffer, add extra days to the lead time. Many teams keep a safety buffer to protect customer commitments.
What is lead time?
Lead time is the total time between when a process starts and when it is completed. In ordering and planning, it often means the time from an order date to a delivery date.
Should I use business days or calendar days?
Use calendar days when commitments are based on total elapsed time. Use business days when work only happens on weekdays. Some organizations also exclude holidays, which vary by company and location.
What does “Include the start date as day 1” mean?
Some teams count the start date as the first day of lead time. Others start counting the next day. If you need that convention, add one day (or one business day) to match your organization’s definition.
Can I share a calculation?
Yes. You can copy the URL after you calculate to share your setup. (This can be added later as a dedicated “Copy share link” button.)
If you’re planning, analyzing, or modeling numbers, you may find these tools helpful as well.