Green Size Calculator
Calculate what size to throw to achieve your desired finished dimensions
Never guess your throwing size again! Enter your desired final dimensions and clay shrinkage rate to see exactly how large to throw your piece.
Calculate Green Dimensions
Green Dimensions to Throw
Enter your desired final dimensions to see what size to throw!
How the Green Size Calculator Works
Enter Desired Final Size
Specify the exact dimensions you want your piece to have after firing.
Set Shrinkage Rate
Enter your clay's shrinkage percentage. Check with your clay supplier for the exact rate.
Get Green Dimensions
See exactly how large to throw your piece to achieve your desired final size.
Throw to Size
Use the calculated green dimensions as your target while throwing or handbuilding.
Frequently Asked Questions
Why do I need to throw larger than my desired final size?
Clay shrinks during firing due to water loss and chemical changes. You must throw larger to account for this shrinkage and achieve your desired final dimensions.
How do I know my clay's exact shrinkage rate?
Check with your clay supplier for the specific shrinkage rate. You can also test by measuring a piece before and after firing, then calculating the percentage difference.
Does this work for handbuilding too?
Yes! Whether you're throwing on the wheel or handbuilding, the shrinkage calculation is the same. Use the green dimensions as your target size while building.
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