What is cycle time

Definition

Cycle time is the elapsed time from the moment work on an item starts to the moment it is finished. The Kanban Guide defines it as "the elapsed time between when a work item started and when a work item finished", and lists it beside three other flow measures: work in progress, throughput and work item age. Waiting before the start belongs to lead time, not to cycle time, but any pause after the start counts, for example an item waiting for a review or for another person. The finish is the team's own definition of done, which can come before delivery to the customer. In manufacturing the same words mean something narrower: the Lean Enterprise Institute defines cycle time as "the time required to produce a part or complete a process, as timed by actual measurement", a measure of one station rather than of a whole work item.

Why it matters

Watching cycle time shows where work stalls once started, because long cycle times usually hide waits inside the process, such as handoffs, approvals or too many items open at once. Its early warning is work item age, the time since an unfinished item started: an item already older than most finished ones is heading for a long cycle time and deserves a look today.

Directly related: Lead Time, Kanban, Scrum.

Formula

Cycle Time = Completion Date - Start Date

Improvement tips

• Agree what counts as started and what counts as done, and write it on the board.
• Look for the waits inside the cycle, such as handoffs, approvals and items parked for someone, before asking anyone to work faster.
• Check work item age every week: an open item older than most finished ones needs attention now.
• Finish before starting: fewer items open at once usually means shorter cycle times.

Common mistakes

• Measuring without an agreed moment for when work starts and when it is done.
• Treating cycle time as hours of effort, when a 10 hour cycle can hold 5 hours of work.
• Promising customers the cycle time, when they wait the whole lead time.