Flow

Lead Time

The total elapsed time from order (or raw material) to delivery (or finished product), including all waiting.

Lead time is the total elapsed clock time for work to move all the way through a process — order to delivery, or raw material to finished good. Critically, it includes queue time and waiting, which usually dwarf actual processing (cycle) time.

Shortening lead time is a primary lean goal because it improves responsiveness, reduces inventory, and exposes problems. Little's Law shows the most reliable lever is reducing WIP.

Go Deeper
WIP / Little's Law Calculator→Little's Law guide→
Related Terms
Cycle Time
The time to complete one unit of work from start to finish at a process — distinct from takt time and lead time.
WIP
Inventory that has entered production but is not yet finished — the lever that controls lead time via Little's Law.
Little's Law
A fundamental relationship: WIP = Throughput × Lead Time, explaining why cutting WIP shortens lead time.
Flow
The smooth, uninterrupted movement of material and information through a value stream with minimal stops or queues.
Throughput
The rate at which a system produces finished, sellable output — ultimately limited by the bottleneck.

Put Lead Time into practice

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