Shrink allowance needs a measured or chosen assumption

Keep the unknown visible

The checked Kona specification establishes 100% cotton and nominal width, not a verified shrink result for your received cut. This site has not performed a wash test or assigned a fixed shrink rate.

Use the correct equation

To retain a chosen finished width after an assumed 5% width shrink, the pre-shrink amount is target divided by 0.95, not merely target multiplied by 1.05. Length and width can have separate assumptions.

Do not turn it into a guarantee

The fabric tool leaves shrink fields empty unless the user supplies assumptions. The result is a scenario; actual material behavior, grain and care conditions still need verification before irreversible cutting.

Model a loss assumption correctly

If you personally choose 5% width loss and need 14 in after that loss, the modeled starting width is 14/0.95, about 14.74 in. Multiplying 14 by 1.05 gives a different result. This inverse calculation is arithmetic only; we have not established that a particular cotton fabric actually loses 5% or shrinks equally in both directions.

Width and length need separate inputs

A hypothetical 14 x 12 in desired cut with 5%assumed width loss and 10%assumed length loss corresponds to about 14.74 x 13.33 in before that modeled loss. The two directions are calculated separately. Equal shrinkage is not inferred from the fabric being cotton. Our defaults remain empty because no verified shrink result for the selected Kona cut was established.

Do not treat an assumption as a test

If you supply 5%because you are exploring an allowance, the resulting number remains an assumption. A measured result would require an appropriate material sample, documented before-and-after dimensions and the exact care conditions. This site has not carried out that procedure or selected a universal test method. Follow the maker guidance before treating a purchased project material.

Avoid counting the same allowance twice

Decide whether your entered rectangle is a desired post-treatment size or already includes a shrink allowance. The optional fields calculate a starting size from the entered target. Entering an already-expanded cut and then adding the same assumed loss again inflates the plan. Record which stage each dimension describes and keep any separate framing or seam allowance visible.

Before you decide

• Keep family, color/SKU and actual quantity
• Separate nominal, usable and assumed measurements
• Read component care and current seller conditions