Inseam Measurement Calculator
Estimate your inside leg measurement from your height, or convert a measured inseam between inches and centimetres.
Last updated · View algorithm, constants and default inputs (JSON)
About this calculator
Inseam is measured from the crotch seam to the hem. Height-based proportions only provide a rough starting estimate; body proportions, garment rise, fit and brand sizing vary. Measure a well-fitting pair when possible.
Worked example
calculated with the default values below
Your height 68 in · Measurement unit Inches · Body proportions Average Estimated inseam 29.9 in · Estimated inseam 76.0 cm · Typical trouser length 30 in
General background references
Disclaimer
These calculators give general estimates. Sizing, pricing, availability and standards vary by brand, retailer and country, so treat the output as a starting point and confirm it against the seller's or authority's own figures.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
I = h × r ; Icm = I × 2.54 ; L = round(I ÷ 2) × 2
- h
- height in inches (cm input ÷ 2.54)
- r
- inseam ratio (short 0.42, regular 0.44, long 0.46)
- I
- estimated inseam (in)
Pants length L is rounded to the nearest even inch; crotch height equals I.
Frequently asked questions
Why does the estimated inseam change with the body proportions selector?
The calculator applies a ratio of height to inseam that varies by body type: 0.42 for short, 0.44 average and 0.46 for long proportions, so a 68-inch tall person gets about 28.6, 29.9 or 31.3 inch inseams respectively. Typical trouser length then rounds the inseam to the nearest even number, and crotch height from the floor equals the inseam, so the selector is the only lever besides height that shifts the result.