Free tools › Rolled throughput yield calculator
Rolled throughput yield calculator
One line per process step: units in, then good units out the first time (no rework). Or a yield, like 97%.
How it is calculated
Each step above passes 95% or better the first time, yet only 87.1% of units make it through all four with no defect. That is why RTY is the yield to improve: it shows the rework and scrap that final yield hides.
Read more: Sigma level and DPMO · Cost of quality · Value stream mapping · DMAIC overview
FAQ
What is the difference between first pass yield and final yield?
First pass yield (FPY) counts only units that pass a step the first time, with no rework. Final yield counts everything that eventually ships, including reworked units. The gap between them is the hidden factory: work you pay for twice.
How is RTY different from overall yield?
RTY multiplies the first pass yields of every step, so it is the chance that one unit goes through the whole process with no defect and no rework. It is always lower than any single step's yield, and it gets worse quickly as steps are added.
What is normalized yield?
The geometric mean of the step yields: RTY raised to the power 1/n. It is the average first pass yield per step, which lets you compare processes with different numbers of steps.
How does RTY relate to DPU?
If defects follow a Poisson distribution, RTY ≈ e^(−DPU), where DPU is total defects per unit across all steps. So total DPU ≈ −ln(RTY).
This shows up on the exams as a calculation question. Practice it with new numbers every time, and every wrong answer explained.
Free Green Belt diagnostic (20 questions)
Free Black Belt diagnostic (25 questions)
Related free tools
DPMO and sigma level calculator · OEE calculator · Takt time calculator · Cpk and Ppk from raw data · All tools
Link to this calculator
Using it in a training deck, an SOP or a forum answer? Copy this link. It stays free.
Try 5 free practice questions with an explanation for every wrong answer.
Take the free CQE quiz