Takt time calculator
Takt time from available time and customer demand, a planned cycle time with an efficiency factor, stations over takt and the minimum number of stations.
Input
The period is whatever the demand covers: one day (1 working day), a week (5) or a month. Other planned stops that are not production time, such as meetings or cleaning, belong in the breaks. The efficiency gives a planned cycle time below takt that leaves room for losses.
Paste, open a CSV, TSV, TXT or XLSX file (up to 20 MB), or drop it on the field. Files are read in this browser only.
Station Cycle time (s) Kitting 41 Screwing 70.5
1 row = 1 station
Columns: tab, ; or ,
Decimals: 12,5 or 12.5
Paste measurements to start.
One row per station with its cycle time in seconds (the work done at the station for one unit). Without stations only takt is calculated.
Runs in this browser. Data is not uploaded or stored.
Results
How takt time is calculated
Takt time is the rate of customer demand turned into time: the available production time divided by the number of units the customer needs in the same period. If every station finishes its work within takt, the line makes what is needed without overproducing; a station slower than takt is a bottleneck before the first part is made.
Formulas
- Available time = shifts per day × (shift length − breaks) × working days in the period.
- Takt time = available time / customer demand in the same period, here in seconds per unit; units per hour at takt = 3600 / takt.
- Planned cycle time = takt × efficiency (or OEE). It is the cycle time to design for, so that the line still meets demand with its usual losses. Optional.
- Minimum stations (or operators) = ⌈Σ station cycle times / takt⌉, and the same with the planned cycle time. Σ cycle times is the work content of one unit.
- Balance = work content / (stations × takt): 100 % means every station is loaded exactly to takt.
- Bottleneck output = ⌊available time / the longest station cycle time⌋: the most units the line can finish in the period if nothing else stops it.
- A station is marked over takt when its cycle time is longer than takt, and over the planned cycle when it fits takt but not the planned cycle time.
Worked example (the tool's example)
- Two shifts of 480 min with 30 min of breaks, 5 days: available time = 2 × (480 − 30) × 5 = 4500 min = 270,000 s.
- The customer needs 4000 units a week: takt = 270,000 / 4000 = 67.5 s, or 53.3 units per hour.
- With an efficiency of 85 % the planned cycle time is 67.5 × 0.85 = 57.38 s.
- The seven stations add up to 358 s of work: at least ⌈358 / 67.5⌉ = ⌈5.30⌉ = 6 stations at takt, ⌈358 / 57.375⌉ = ⌈6.24⌉ = 7 at the planned cycle time. The line has 7, so the balance is 358 / (7 × 67.5) = 75.8 %.
- Screwing takes 70.5 s, more than takt: the line can make at most ⌊270,000 / 70.5⌋ = 3829 units a week, short of 4000. Wiring (58.5 s) and function test (64 s) fit takt but not the planned cycle time.
Common mistakes
- Using the shift length without taking off breaks and planned stops: takt comes out too long and the line too slow.
- Taking demand and available time from different periods (a weekly demand with a daily time).
- Designing stations to exactly takt: every stop then becomes lost output. Plan to a cycle time below takt.
- Reading the minimum number of stations as the answer: it assumes the work can be cut anywhere. Task times and their order decide the real number; see line balancing.
- Confusing takt (a customer pace, the same for every station) with lead time (how long one unit takes through the whole line).
Input and files
- Numbers may use a decimal comma or point. Breaks and efficiency may be left empty; the station list too.
- Station columns are found by their header names (Station, Cycle time), otherwise the label column is the station and the rightmost number column the cycle time.
- Files: CSV, TSV and TXT are read as if pasted (UTF-8, UTF-16, otherwise Windows-1257). XLSX: choose the sheet and the columns or a cell range; formula cells use the value Excel last saved, dates are kept as text. Files up to 20 MB are read in this browser only and never uploaded.
- XLSX files are read with SheetJS Community Edition 0.20.3, Apache License 2.0 (license text at the end of this file).
Questions
- What is the difference between takt time and cycle time?
- Takt time comes from the customer: the available time divided by the demand, the pace at which one unit must be finished. Cycle time comes from the process: how long a station or the line actually takes for one unit. A station whose cycle time is longer than takt cannot keep up with demand.
- Should the cycle time be equal to takt?
- No, a little below it. Breakdowns, changeovers, minor stops and rejects take time that takt does not include, so lines are usually planned to a cycle time of takt multiplied by an efficiency or OEE factor, for example 85 %.
- Are breaks part of the available time?
- No. Available time is the time the line is meant to produce: shift length minus breaks, and minus other planned stops such as meetings or cleaning. Unplanned stops are not taken off; they are covered by the efficiency factor.
- How many operators or stations do I need?
- At least the total work content divided by takt, rounded up. That is a lower bound: if the work cannot be split evenly, or the order of the tasks does not allow it, more stations are needed. The line balancing tool assigns tasks to stations with their precedence.