Takt time is a commonly used metric in Lean manufacturing for effectively managing a pull system. The concept was first used as a project management tool by the German aircraft industry, eventually becoming popularized by Toyota and the Toyota Production System. Takt time is the maximum amount of time needed to completely manufacture a product from start to finish while fulfilling customer demand. Calculating takt time is done with the following formula:
T = Ta÷ D
In this equation, Ta represents available production time. This is not the total time in a shift, but rather takes into account breaks and planned stoppages. D then represents the rate of customer demand in the formula. Simply take available production time and divide that number by demand to end up with takt time.
Let’s look at an example of a factory producing specialty tubes of toothpaste. First, we’ll determine total available production time. In eight-hour day employees have a 30-minute lunch break and two 15-minute breaks, making available work time 35 hours a week or 2,100 minutes. Approximately 100 orders are placed every day which brings the weekly rate of customer demand 1,500 units. Using the above formula above, 2,100 minutes is divided by 500 for a takt time of four minutes and 12 seconds.
So, what does this number mean? In order to adequately meet customer demand and maintain a smooth level of production, the toothpaste factory will need to make about one tube of toothpaste every four minutes and 12 seconds.
Takt time is a relatively static measurement as it represents the capacity of the production line. It’s not an exact science and you will want to reevaluate periodically. Knowing and understanding takt time however can help greatly when making key decisions, optimizing your workplace, maintaining continuous flow, and avoiding overproduction.