Measure twice, make once
Blocking change projection
Project finished dimensions from the measured change in your blocked swatch.
The page shows its formula, example, assumptions, rounding, and limitations beside the calculator.
Blocking change projection
Project finished dimensions from the measured change in your blocked swatch.
Formula and assumptions
Width and height use their own measured after-to-before ratios. This is a projection from your swatch, not a safe stretching target.
Worked example
Example: a swatch changing from 10 × 10 cm to 11 × 9 cm projects a 50 × 60 cm piece to about 55 × 54 cm.
Limits and rounding
Results are planning estimates from the values entered. Displayed decimals are rounded for craft use; whole materials and repeats round up where the method says so. Confirm gauge, material behavior, construction, and finished measurements before committing supplies.