Die Size Calculator
Enter the wafer diameter, the die width and height, the scribe line width, the edge exclusion and, if you know it, the defect density. The calculator estimates the dies per wafer, the yield and the good dies.
- Dies per wafer
- Yield
- Good dies
Defect density D₀ is in defects per cm². Leave it at zero to skip the yield.
Smaller dies fit far more per wafer, with less waste at the edge. The usual estimate is π(d/2)² ÷ A − πd ÷ √(2A). A 10 × 10 mm die on a 300 mm wafer, with a 0.1 mm scribe and 3 mm edge exclusion, gives about 600 dies. At 0.1 defects per cm², about 90% are good, so 542.
Dies per wafer chart
Square dies, 0.1 mm scribe, 3 mm edge. Search for a die size.
| Die (mm) | 150 mm | 200 mm | 300 mm |
|---|---|---|---|
| 2 × 2 | 3540 | 6497 | 15082 |
| 3 × 3 | 1591 | 2936 | 6853 |
| 5 × 5 | 563 | 1051 | 2481 |
| 7 × 7 | 278 | 525 | 1254 |
| 10 × 10 | 127 | 247 | 600 |
| 15 × 15 | 50 | 101 | 254 |
| 20 × 20 | 24 | 51 | 135 |
| 26 × 26 | 11 | 26 | 74 |
Gross dies.
Die size and count
300 mm wafer. Slide the die size.
The wafer map shows the whole dies that fit.
How to estimate dies per wafer
Die to count. Step through it.
Wafer
Usable diameter.
Rectangular dies close to square usually waste least at the edge.
150, 200 or 300 mm wafers
Wafer sizes. Compare them.
Six inch.
Eight inch.
Twelve inch.
A 300 mm wafer has 2.25 times the area of a 200 mm wafer, but often gives more than 2.25 times the dies because less is lost at the edge.
Before you plan
Die checks. Tick each item.
Tick each item as you go.
Test structures and alignment marks can take up space on a real wafer.
What you get
Die count. Each tile explains one result.
Per wafer.
Percent.
Count.
mm².
Diameter.
Big dies lose much more to defects, as each defect kills a bigger share of the wafer.
Frequently Asked Questions
No question matches that search.
How many dies fit on a wafer?
Use the wafer area divided by the die area, less an edge loss term, which this calculator applies.
What is a scribe line?
The gap between dies where the wafer is cut apart.
What is edge exclusion?
A ring at the edge of the wafer where no good dies are made.
How is die yield estimated?
A common model is e to the power of minus defect density times die area.
Why do larger dies have lower yield?
Each defect is more likely to land on a big die.
How big is a three hundred millimetre wafer?
About seven hundred and seven square centimetres.
Is the formula exact?
It is a close estimate. A real wafer map can differ by a few dies.
Plan the wafer
Estimate the dies and yield early, and the cost of every chip is much easier to predict.
More size calculators
Each one has its own calculator, worked examples and answers to common questions.