How to calculate takt time
Takt time is the pace the customer sets for the plant. It does not depend on machines or operators, only on how much time you have and how many units you must deliver in that time.
Takt time = available time ÷ demand
- Available time: shift length minus planned breaks, times the number of shifts.
- Demand: how many units the customer needs in the same period (per day, per week).
Always use the same time base on both sides. If demand is daily, available time is daily too.
Worked example
The values already filled in the calculator:
- 480 min shift with 30 min of breaks: 450 min available per shift
- 2 shifts: 900 min, or 54,000 seconds per day
- Demand of 900 units per day
Takt = 54,000 s ÷ 900 = 60 seconds per unit. The line has to deliver one unit a minute, or 60 an hour.
Now compare with the real line. The slowest station takes 66 seconds:
- The cycle is 10% over takt, so the line cannot keep up with demand.
- At the current cycle it makes 54,000 ÷ 66 = 818 units a day. It is 82 short.
- Closing the gap would take about 90 minutes of overtime every day.
The total work content per unit is 240 seconds: 240 ÷ 60 = 4 stations at minimum. If the line already has 4 stations and one of them runs at 66 seconds, the problem is not headcount, it is balance: too much work on one station and slack on the others.
Takt time vs cycle time vs lead time
| Metric | Comes from | Question it answers |
|---|---|---|
| Takt time | customer demand | What pace do I need? |
| Cycle time | the process (slowest station) | What pace can I run? |
| Lead time | the whole flow, queues and inventory included | How long does one unit take from start to shipping? |
The rule of thumb: cycle ≤ takt at every station, with some margin. Many plants plan stations at 85–95% of takt to absorb minor stops and variation.
From takt to line balancing
Takt is where a line balance chart, or Yamazumi, starts. You stack the operation times of each station and draw a horizontal line at takt:
- Time the operations at each station (time study).
- Separate value-adding work from the rest.
- Stack them per station and compare with the takt line.
- Move work from stations over takt to stations with slack until all are under it.
Line balance efficiency is total work content ÷ (number of stations × slowest station’s cycle). In the example above, 240 ÷ (4 × 66) = 91%.
Common mistakes
- Subtracting breakdowns from available time. Breakdowns are losses, not unavailable time. Subtracting them makes takt tighter than demand requires and hides the problem.
- Mixing up takt and cycle. Takt is the target; cycle is reality.
- Calculating takt once and never again. Demand changes, and takt changes with it.
- Planning stations exactly at takt. With no margin, any few-second stop becomes a delay by the end of the shift.