Pot Drop Calculator

Enter any two of the values below,
select your glass, and click "Go!"


How to use this calculator


This calculator assumes your pot drop will be a circle. You can specify the target size by diameter (distance across the middle of the circle) or by circumference (distance around the circle).


Most glass will usually try to be about 5 mm thick when left to its own under full fuse temperatures. Thicker pieces can be achieved by damming the glass.


Probably the most useful scenario for this tool is determining the amount of glass needed for a desired size pot drop. When solving for weight, you can still set the unit of measure (grams or ounces) and your results will be displayed in that unit.


Soda-lime glass includes most popular art glasses including Bullseye, Spectrum, Uroboros and float. If you aren't sure what kind of glass you have it is probably soda-lime.

pot drop calculator

Looking forward to using the calculator. 

~Celeste  :)


How useful - thank you, thank you!

Pot Drop

What is a pot drop?


Mary Beth

Thank you!

I've used the calculator twice and both times the results were spot on!  What an anxiety reliever.  Many thanks!

pot calculator

pam tandon

Please I have a question when using the pot melt calculation how does one know what  is the length of the pot made to be kept. I have a mold with a hole 3 inches.

I will be doing it for the first time . I am in New Delhi India and here glass fusing is very new  in fact I can say I am one of the first ones to do it and I am just doing my trials. I imported my skutt kiln., and even Bulls eye glass had to be imported.

I do need a lot of guidence.

thank you

pot calculator


Hope I understand what you mean by "length of the pot to be kept".  It sounds like you're trying to plan for the final piece.  First you make the "pot melt" THEN you kiln form that into the piece to be kept.  This calculator is designed for the first part.  It's intent is to take the guess work out of knowing how much glass to use to get a certain size (if the glass is left unrestrained).  So, for example, if you are planning to use a mold or drop ring in the second step I'd suggest using its diameter to guide your use of the pot melt calculator so you get a size that works with that mold or drop ring.  The length or height of your final piece is a separate issue involving the thickness of the glass.


I want to be sure this calculator will work for 96 coe.  It was dismaying when I learned my handy EZ Fuse cd wouldn't work on our new MAC.  So, I'm very hopeful I'll be able to use this one.

Pot Melt Calculator

I have used this calculator many, many times.  It is very accurate.  It even accounts for the residue left in the pot.  I work in System 96 and my 'puter is a MAC.  You may proceed with confidence!

glass calculator

this is awesome!

do you have one for a scrap melt into a dammed square or rectangle?

The casting calculator will

The casting calculator will do that. It is under the tools menu.

Helios Kiln Glass Studio


great! thanks.  

great! thanks.


Pot Drop Calculator

Will this calculator work for screen melts also?


Big Help!

After ten years happily glassfusing, I am now ready to do my first pot melt. I read your book (legally bought, of course) and there I got the tip about this calculator. What a big help! Now it´s up to me ... fingers crossed!


ot melt calculator assumptions

When working with a 12" diameter SS.circle, does your calculator take into account the 1/8" fibre liner inside the circle?  In other words, should I specify a 11.75" circle rather than a 12" one?

In recent potmelts, I had been using 37 OZ of glass and getting the result weighing 37 OZ afterwards,maning that all the glass had been consumed. However, the resltant glass has shrunk and runs about 11 3/8" in diameter.  What am I doing wrong?



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