Case 1
- Order processing time
- 3d
- Production time
- 10d
- Shipping and transit time
- 7d
20.0d
Open with these valuesLead Time Calculator
20.0days
Result: 20.0 daysLead time is the sum of its stages: the days until your supplier starts, the days of production, and the days in transit. Three, ten and seven make twenty days. Keep all three on one basis, calendar or working days, because the calculator adds them exactly as you enter them.
The numbers at a glance
Held fixed: Order processing time 3.0 d, Production time 10.0 d.
| Shipping and transit time (d) | Result (d) |
|---|---|
| 0.0 | 13.0 |
| 2.0 | 15.0 |
| 4.0 | 17.0 |
| 6.0 | 19.0 |
| 7.0Your value | 20.0 |
| 8.0 | 21.0 |
| 10.0 | 23.0 |
| 12.0 | 25.0 |
| 14.0 | 27.0 |
Worked examples
Case 2
- Order processing time
- 5d
- Production time
- 0d
- Shipping and transit time
- 14d
19.0d
Open with these valuesCase 3
- Order processing time
- 2d
- Production time
- 0d
- Shipping and transit time
- 3d
5.0d
Open with these valuesHow it's calculated
Lead time = order processing + production + transit
- StepEnter the days from placing the order until the supplier starts work.
- StepEnter the days of production; goods shipped from existing stock take 0.
- StepEnter the days in transit, including customs and last-mile delivery.
- ResultRead the total in days, and divide it by 7 for calendar weeks.
Reference table
| Processing, production, transit | Typical situation | Lead time |
|---|---|---|
| 0, 0, 0 | Picked off your own shelf | 0 |
| 2, 0, 3 | Stock item, domestic courier | 5 |
| 5, 0, 14 | Stock item, sea freight | 19 |
| 3, 10, 7 | Made to order, air freight | 20 |
| 5, 20, 35 | Overseas production, sea freight | 60 |
Questions
What is lead time?
Lead time is the total time between placing an order and having the goods ready to use or sell. In a supply chain it is the sum of three stages: order processing until the supplier starts, production, and transit to you. Three, ten and seven days make a lead time of twenty days.
How do I calculate total lead time?
Add the time for each stage, all in the same unit. Total lead time is order processing plus production plus transit, so 3 plus 10 plus 7 is 20 days. If a stage does not apply, because you ship from existing stock and nothing is made, enter 0 for it.
How do I convert lead time into weeks?
Divide the total in days by 7, so a 20-day lead time is about 2.9 weeks. Weeks are often easier to agree with suppliers and to slot into a production plan. Note that this divides by calendar weeks, not five-day working weeks.
Should I use working days or calendar days?
Use whichever your suppliers quote, but stay consistent across all three stages. Production is often quoted in working days while transit runs on calendar days, so convert everything to one basis first. Mixing them makes the total wrong, and calendar days give the more conservative estimate.
How can I shorten the lead time?
Shorten any one of the three stages, because they simply add up. Standing orders and pre-approved paperwork cut processing, reserved capacity cuts production, and air instead of sea cuts transit. A shorter chain lets you hold less stock, which frees cash and warehouse space.
Sources and last check
Information, not professional advice.