Cycle time calculation: the formula, with a shop-floor example.
Cycle time is the heartbeat of a production line: how often a finished part drops off the end. Get it right and you can promise a delivery date with confidence. Get it wrong and you either miss the schedule or pile up inventory you cannot ship.
What cycle time means
Cycle time is the actual time between one completed unit and the next coming off a process or line. It is a measured output, not a target. If a CNC cell finishes a part every 90 seconds, the cell cycle time is 90 seconds — regardless of what the customer needs or what the machine could theoretically do.
Engineers mix up three related terms, so pin them down first:
- Cycle time — how often a unit is completed (what you measure).
- Takt time — how often you must complete a unit to meet demand (what the customer sets). Covered in detail in the takt time guide.
- Lead time — total elapsed time from order to delivery, which includes queueing and is much longer than cycle time.
The cycle time formula
There are two views you will use constantly:
- Process cycle time — for a single station: the time that station takes to complete one unit.
- Line cycle time — for a multi-station line: it equals the cycle time of the slowest station, the bottleneck. The line cannot run faster than its slowest step.
That second point is the one shop floors forget. Adding capacity to a fast station does nothing for output; only the bottleneck moves the line.
A worked example
Take a small assembly line in a Coimbatore pump shop running one shift.
| Input | Value |
|---|---|
| Shift length | 8 hours = 480 min |
| Planned breaks | 2 × 15 min + 30 min lunch = 60 min |
| Changeover / setup | 20 min |
| Net production time | 480 − 60 − 20 = 400 min |
| Units produced in shift | 250 pumps |
Apply the formula:
Now suppose the customer needs 300 pumps a day. Takt time = 400 min ÷ 300 = 1.33 min/unit (80 seconds). Your cycle time of 96 seconds is slower than the 80-second takt, so at the current pace you fall short by 50 pumps a day. The gap tells you exactly how much you must improve the line.
Cycle time vs takt time: reading the gap
| Situation | Meaning | Action |
|---|---|---|
| Cycle time > takt time | Too slow — you miss demand | Improve the bottleneck |
| Cycle time = takt time | Balanced — demand met exactly | Hold and stabilise |
| Cycle time < takt time | Faster than needed | Risk of overproduction; redeploy capacity |
The aim is not the lowest possible cycle time. It is to sit cycle time at or just below takt, with a small buffer for reliability. Running far below takt builds inventory that ties up cash and floor space — one of the classic seven wastes.
Find the bottleneck first
Because line cycle time equals the slowest station, the whole improvement game is bottleneck hunting. A quick method:
- Time each station's per-unit cycle (average several cycles, not one).
- Plot them as a bar chart against takt time.
- The tallest bar above takt is your constraint. Fix it, then re-measure — the bottleneck usually moves to the next station.
How to reduce cycle time
- Balance the line. Move work content from the bottleneck to lighter stations so cycle times even out near takt.
- Cut setup with SMED. In the example, the 20-minute changeover eats production time. Halving it adds run time directly.
- Remove non-value-added motion. Walking, reaching and searching inflate station cycle time without adding value.
- Attack waiting. A station starved of parts or waiting on an inspection sits idle. Smooth the upstream feed.
- Improve the slowest operation only. Spending money on a non-bottleneck station is wasted capital.
Cycle time also feeds directly into OEE: the performance term in OEE compares your ideal cycle time to actual run rate, so a reliable cycle time figure is the starting point for any OEE programme.
If your bottleneck is the inspection step rather than the machine, the slow part is usually manual measurement and paperwork. Tools like CadNexa's auto-ballooning turn a drawing into a numbered inspection sheet in minutes, which takes the inspection station off the critical path.
Frequently asked questions
What is the cycle time formula?
Cycle time equals net production time divided by the number of units produced in that time. For example, 400 minutes of run time producing 250 parts gives a cycle time of 1.6 minutes per part.
What is the difference between cycle time and takt time?
Cycle time is how fast you actually produce a unit. Takt time is how fast you must produce to meet customer demand. To meet demand without overproducing, cycle time should be equal to or just below takt time.
How do you reduce cycle time?
Balance the line so no single station is a bottleneck, cut non-value-added motion and waiting, run setup reduction (SMED), and improve the slowest operation first. The bottleneck station sets the line cycle time.
Is lower cycle time always better?
No. Producing faster than takt time builds inventory you cannot sell yet, which ties up cash and floor space. Match cycle time to takt time with a small buffer rather than chasing the lowest number.