Explore guide
Project finished dimensions from a before-and-after sample
A sample changing from 10 × 10 cm to 11 × 9 cm grows 10% in width and shrinks 10% in height. A comparable 50 × 60 cm piece projects to 55 × 54 cm.
Related lessons and tools
A sample changing from 10 × 10 cm to 11 × 9 cm grows 10% in width and shrinks 10% in height. A comparable 50 × 60 cm piece projects to 55 × 54 cm.
Work through the example
- Mark the same measured area before treatment. Record both axes without stretching the sample.
- Use the actual intended washing, drying or blocking method, then let the sample reach its final dry condition before remeasuring.
- Enter both sets of sample measurements and the unfinished project dimensions. Keep the width ratio and height ratio separate.
- Compare the projected 55 × 54 cm with the required finished size. If it is unsuitable, change the plan and sample again rather than forcing the final piece to size.
- Save the treatment details, dimensions and observed fabric changes with the project. Measure the finished piece to check the estimate.
Check before committing
Small-sample ratios do not guarantee garment behavior under its own weight. Mixed structures and different fibers may require several separate samples.
Printable planning record
Inputs and sample measurements recorded; chosen result checked; material/color references recorded; reserve included once; construction and finishing checks completed.
Method and sources
These are original planning examples using the linked tools’ methods. Replace measured inputs with your own samples; a calculator cannot validate the construction. Keep the resulting measurements, choices and remaining checks with the project.
Blocking change projection
Project finished dimensions from the measured change in your blocked swatch.
Before you use this tool
Measure the same marked sample before finishing and again when completely dry and rested. Keep width paired with width and height with height.
The result predicts comparable fabric behavior; it is not an instruction to stretch a project to those dimensions.
Method and limits
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.