What is lead time?
Lead time is the total elapsed time from when a work item is requested or created to when it is delivered to the customer or marked complete. It includes every stage of the process: time spent waiting in the backlog, time spent in active development, time in review, and time waiting for deployment. Lead time measures the full customer-facing delay, not just the active work portion.
Lead time is distinct from cycle time, which only measures the active work period. If a feature request sits in the backlog for two weeks before an engineer picks it up and completes it in three days, the cycle time is three days but the lead time is 17 days. Both metrics are useful, but lead time is what the person who requested the work actually experiences.
Why lead time matters
Lead time is the metric that most closely reflects how responsive a team is to its users, customers, or stakeholders. A team can have excellent cycle times - finishing each task quickly once started - while still having long lead times because work sits in the backlog for weeks before being picked up. Monitoring lead time reveals the full picture: how long does it actually take from request to delivery?
Reducing lead time requires looking beyond the active work phase. Common sources of lead time inflation include large backlogs where items wait weeks before prioritization, handoff delays between teams, slow review processes, and manual deployment steps. Addressing any of these reduces lead time even if the actual development speed stays the same.
Lead time vs. cycle time
The simplest way to think about the distinction: lead time is the clock that starts when the customer asks for something, while cycle time is the clock that starts when the team begins working on it. The gap between lead time and cycle time is queue time - the period where work is waiting but no one is actively touching it. For most teams, queue time is the largest component of lead time, which is why reducing backlog size and grooming frequency has an outsized impact on delivery speed.
How Flux supports lead time tracking
Flux's event-sourced activity log records the timestamp of every card state change - when a card was created, when it moved into each column, and when it reached the Done column. This trail of timestamps provides the raw data needed to calculate lead time for any card. Teams can see how long each item took from creation to completion, and identify patterns like cards that spent disproportionate time waiting in a particular column. Marking a column as Done establishes a clear completion boundary for lead time measurement.
Related terms
See also: Cycle Time, Throughput, Backlog.