Capacity and utilization calculator
Enter the available time, the bottleneck cycle time and the demand: it tells you whether the line makes it and with what margin.
Capacity
80.0
Required utilization
75.0%
Margin (units)
20.0
Capacity covers demand with room to spare. Careful: spare capacity is not a goal, it is idle capital. The preloaded values are the croissant-factory example from the UNGS book: baking, the slowest station, takes 6 min per dozen, so an 8-hour day yields 80 dozen.
How it works
You enter the available time, the bottleneck cycle time (the slowest station) and the demand to meet.
- Capacity = available time ÷ bottleneck cycle time.
- Required utilization = demand ÷ capacity.
- Margin = capacity − demand (negative if units are missing).
Above 100% the demand is not reached; if utilization is 90% or more, you make it but with almost no margin for stoppages or peaks. That 90% warning is a rule of thumb of this site. The croissant-factory example from the UNGS book is preloaded: baking, at 6 minutes per dozen, sets 80 dozen per day. Utilization close to 100% is not a goal: it leaves no room for the unexpected.
If you prefer to work in Excel, there is a takt time and capacity per workstation spreadsheet in Excel with these same calculations.
Sources
These are the ones from the article where the theory behind this tool is developed.
How does production capacity differ from selling capacity? It is in the article Production capacity vs. demand and utilization rate.