Derive signed length and width change from one measured fabric specimen, then apply its retained ratios to a finished-dimension scenario.
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Derive signed length and width change from one measured specimen and apply the retained ratios to an entered finished-dimension scenario without turning one sample into a care rule, lot guarantee or fit decision.
Replace a generic shrink percentage with measured before/after marks.
Record specimen identity and treatment, enter both directional measurements, then inspect contraction, retained ratios and projected untreated scenario dimensions.
Can reproduce the signed record and keeps it tied to that specimen and treatment.
See growth and mixed-direction behavior instead of forced “shrinkage.”
Run contraction, zero, growth and mixed cases using the same documented measurement protocol.
Can classify the observation without negative finished dimensions or hidden absolute values.
Know what evidence the arithmetic cannot supply.
Reconcile specimen and whole-item/component testing with the applicable pattern, care-label and product requirements.
Does not issue a care instruction, certification, fit claim or cutting approval from one Tool run.
Outputs and checklists are planning aids. Review the linked current authorities and the records, terms, instructions, and requirements that apply to your exact situation before a consequential decision.
This tool is part of these guided projects. Each project provides step-by-step instructions with checklists and all the tools you need in one place.
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Measure between the same marked points before and after one documented treatment and conditioning process. Negative change means contraction; positive change means growth.
change% = (after − before) / before × 100Length and width are kept separate because one specimen may contract, remain unchanged, or grow differently in each direction.
retained ratio = after / beforeDivide an externally established required finished dimension by the measured retained ratio. This is a scenario tied to one specimen, not a fit, care, cutting, lot or quality approval.
required untreated dimension = required finished dimension / retained ratioUpdated: August 2026
A marked 12×12-inch specimen measured 11.4×11.64 inches after the recorded treatment: −5% length, −3% width, with both ratios retained.
If an after-treatment measurement is larger, the Tool reports a positive percentage and a growth state instead of calling it negative shrinkage.
Length contraction with width growth remains visible as a mixed state; the Tool never collapses two directions into one absolute shrink number.
Enter actual before and after dimensions from the same marked specimen and treatment; fiber name alone does not establish lot or finished-item behavior.
Retain material/lot, directions, marks, treatment, conditioning, repeat and whole-item/component evidence, then follow applicable pattern, manufacturer and regulatory requirements.
This Tool records signed dimensional change observed in one marked specimen after one documented treatment and conditioning process. It keeps length and width separate and applies those retained ratios to an explicitly entered finished-dimension scenario. It does not prescribe prewashing, care, fit, ease, cutting, labeling, certification or behavior for a whole lot, component assembly or future cycle.