ClayFit: Clay ShrinkageClayFit: Clay Shrinkage
Track your clay, not the numbers on the bag.
Download on the App Store
Screenshots
Features
Your data, accumulated over time
Record shrinkage from each firing, and ClayFit builds your clay database. It averages your measurements, shows you how many test bars that comes from, and flags the ones that look wrong.
Work backwards from finished size
Tell it the mug should be 90 mm wide after glaze firing. ClayFit calculates the wet diameter, shows the shrinkage rate it used and how solid that rate is.
Every stage gets measured
Record wet, bone-dry, bisque, and final. Track shrinkage at each step, or record the wet size today and add the rest later. The app shows cumulative shrinkage automatically.
Volume backwards too
Linear shrinkage happens in three directions. Tell ClayFit the final bowl should hold 500 ml, and it calculates the wet volume you need.
Every clay body shrinks. Yours does not shrink by the number on the bag — it shrinks by whatever your clay, your kiln and your firing schedule actually do. ClayFit measures that, remembers it, and works backwards from the size you want.
YOUR CLAY, NOT THE CATALOGUE
Manufacturer figures are a starting point. The rate you get depends on the batch, the bisque, the cone you fire to and the atmosphere in the kiln. ClayFit stores a measured shrinkage rate for each clay and each firing profile, built from test bars and finished pieces you measured yourself.
WORK BACKWARDS FROM THE FINISHED SIZE
You know the mug should be 90 mm across when it comes out of the glaze firing. ClayFit tells you how wide to throw it wet. Enter a target and it gives you the wet dimension, using your own measured rate — and it shows you the rate it used, how many measurements it came from, and how much those measurements varied.
EVERY STAGE, NOT JUST THE TOTAL
Record a test bar wet, then bone dry, then after bisque, then after the final firing. ClayFit works out the shrinkage at each step and the total from wet to fired. Enter the wet measurement today and come back weeks later to add the rest — the record waits for you.
VOLUME TOO
A 500 ml bowl fired is not a 500 ml bowl wet. Linear shrinkage compounds in three directions, so ClayFit does the cube for you and tells you the wet equivalent volume to aim for.
WHAT YOU GET
• Unlimited firing profiles and measurements per clay
• Average shrinkage with sample count and spread, so you know how solid it is
• Reverse calculator for diameter, width, height, length and volume
• Round up to your preferred step, because short is worse than long
• Outlier detection — impossible readings are flagged and left out
• Home Screen widget showing your active clay and its rate
• mm, cm or inches; ml, litres or fluid ounces; Celsius or Fahrenheit
• Everything stays on your device. No account, no network, no tracking
The Unlimited upgrade is a one-time purchase, not a subscription. It removes the clay-body limit and adds CSV export.
ClayFit gives estimates based on the measurements you enter. Real pieces vary with wall thickness, throwing, drying and where they sit in the kiln. Test bars are still the honest way to check a new batch.