Estimate 3D printing yield loss from the difference between total printed parts and parts accepted as good. The calculator reports rejected units, first-pass yield, loss rate, and an optional material/processing cost impact when a cost per rejected part is entered.
This view is useful when failed builds, dimensional defects, surface issues, or post-print inspection reduce the usable quantity from otherwise completed production. Tracking both the percentage loss and the absolute rejected count helps distinguish a small rate on a large production run from a high failure rate on a small batch.
Inputs
parts
parts
USD
Result
—
yield loss rate
Rejected parts—
First-pass yield—
Estimated reject cost—
1. Enter total printed parts Count all parts that completed the printing stage for the period or batch being reviewed.
2. Enter accepted good parts Use the quantity that passed your defined acceptance criteria.
3. Add reject cost if useful Enter an estimated cost per rejected part to translate the loss count into a simple cost impact. Leave it blank or at zero if cost is not needed.
4. Review the loss rate The main percentage is rejected parts divided by total printed parts.
5. Check yield and rejected count Use first-pass yield and absolute rejected units to understand both quality rate and volume impact.
Formula:
Rejected parts = Total printed parts − Good parts
Yield loss rate = Rejected parts ÷ Total printed parts × 100
First-pass yield = Good parts ÷ Total printed parts × 100
Estimated reject cost = Rejected parts × Cost per rejected part
Total and good counts must cover the same production boundary and time period. The optional cost is a simple per-unit estimate and can represent material plus allocated processing cost if you define it that way.
Rework is not separately modeled. A part counted as rejected here is treated as lost output unless your counting policy classifies successfully reworked parts as good.
What the result means
The main result is the percentage of completed printed parts that did not qualify as good output under your acceptance rules.
Keep the defect and rework counting policy consistent from period to period so trends remain comparable.
Given: 250 total printed parts, 232 accepted good parts, and an estimated $4.50 cost per rejected part.
Result: Yield loss is 7.20%, equal to 18 rejected parts and an estimated $81.00 in reject cost.
The rate shows the quality loss relative to output, while the dollar estimate adds a rough economic view based on the cost definition used.
Should a failed full build be counted part by part?
Use the same unit basis as your total production count. If the build contained 20 intended parts and all 20 are treated as produced rejects under your tracking system, count 20; if your system records failed builds separately, use a build-based analysis instead.
What is the difference between yield loss and first-pass yield?
They are complementary under this simple model. If all output is classified as either good or rejected, yield loss plus first-pass yield equals 100%.
How should reworked parts be handled?
Choose a consistent policy. If the metric is first-pass yield, parts requiring rework normally are not counted as first-pass good even if they later become usable.
What should I include in reject cost?
Use a definition that matches your purpose, such as material only or material plus printer time and direct labor. The calculator multiplies the entered per-part amount and does not build up those cost components separately.
Can I compare loss rates across different materials or printers?
Yes, but make sure acceptance criteria and counting rules are comparable. Differences in geometry, material difficulty, or inspection standards can explain rate changes that are not caused by the printer alone.