Throughput is how much you actually make in a given time. Throughput = good units made ÷ time. A kitchen that packs 1,800 pierogi in a 7-hour day has a throughput of about 257 an hour. The useful part comes from looking at each step: forming, boiling, freezing and packing each have their own rate, and a line can't go faster than its slowest step, the bottleneck. Speed up any other step and nothing more comes out the end. Throughput is different from capacity, which is the most a step could do if nothing went wrong, and from takt time, the pace your orders call for. When throughput falls short of what orders need, the fix is at the bottleneck: another person, another tray, or a change to how that one step is done. In the example below, a pierogi maker works out its line's throughput before saying yes to a bigger grocery order.
The short version
- Throughput = good units made ÷ time, counted at the end of the line.
- Work out each step's rate: units it can handle per hour.
- The line runs at its slowest step, the bottleneck.
- Speeding up any other step adds nothing.
- Capacity is the most possible; throughput is what you got; takt is what orders need.
- Count only good units: rejects aren't throughput.
- TaroStack records each batch's yield and labor minutes, and plans against work center hours. More below.
The formulas
| Measure | Formula |
|---|---|
| Throughput | Good units made ÷ hours |
| Each step's rate | Units the step handles ÷ hours it takes |
| Line throughput | The lowest step rate |
| Hours to make an order | Units needed ÷ line throughput |
| Throughput time | How long one unit takes from start to finish |
How much a kitchen could make at best is in how to calculate production capacity, and the pace orders set in takt time formula.
An example: a pierogi kitchen's day
Avondale Pierogi Co., a made-up pierogi maker in Chicago, Illinois, makes frozen dozens in a shared kitchen. Forming by hand with a mold takes 40 seconds a pierogi, so one person forms 90 an hour. Its line, with three people forming:
| Step | How it works | Rate per hour |
|---|---|---|
| Forming | 3 people × 90 an hour | 270 |
| Boiling | 100 pierogi every 8 minutes, kettle and cooling rack | 750 |
| Freezing | 600 on the freezer racks, 2 hours to freeze | 300 |
| Packing | 1 person, 25 dozen an hour | 300 |
| Line | The slowest step: forming | 270 |
At 270 an hour, the 150 dozen, 1,800 pierogi, that the kitchen makes on a production day take 6 hours 40 minutes. A grocer's new order needs 50 more dozen on each production day. A fourth person forming would lift forming to 360 an hour, but the freezer racks would then hold the line at 300, so the owner added a fourth former and a second set of racks together: forming 360, freezing 600, and packing becomes the slowest step at 300. The 200 dozen, 2,400 pierogi, now take 8 hours at 300 an hour, a long day but one day. What the dozens cost is in pierogi business plan.
Get the calculator
Download the throughput calculator. One sheet: type each step's name, units per cycle, minutes per cycle and how many people or machines run it; each step's rate per hour, the line's throughput and its bottleneck fill in, with the hours to make an order of the size you type. It's an ordinary Excel file with no macros, and it works in Google Sheets, LibreOffice and Numbers.
Where this stops working
The calculator assumes every step runs at its rate all day. Real days have a late flour delivery, a batch of dough that had to be remade, and a former who's out, and the only way to know the real throughput is to record what each batch made and how long it took.
How TaroStack does it
TaroStack records what each batch really made and how long it took, and plans against the hours you have.
Batches with yield and labor. Each batch records what it made against what the recipe expected, and the labor minutes it took, so the real throughput of a production day is on record.
Recipe truth. From your own batch history, TaroStack shows whether a recipe yields what it claims.
Capacity against hours. Work centers have hours, so a week's production plan doesn't promise more forming time than the kitchen has.
| The job | Clipboard | In TaroStack |
|---|---|---|
| What a day really made | Counted at the end | Each batch's yield |
| How long it took | Remembered | Labor minutes on the batch |
| Whether a recipe yields what it says | A hunch | Recipe truth from batch history |
| Whether next week fits | Guessed | Plan against work center hours |
Recipes and batches are on every plan, from $49 a month; planning against work center hours is on Standard, at $99 a month. The first 30 days are free, with no credit card. If you'd like a hand setting up, ask, and we'll do it with you.