Blog / Category
Sizing & Fit
The engineering of clothing size recommendation — brand normalization, international conversion, fashion e-commerce sizing flows, and the science behind why clothes don't fit.
29 articles · ← All categories
Build vs. Buy: Adding Size Recommendations to Your App Without Training a Model
Build vs. buy for size recommendation engines — data requirements, ML infrastructure, accuracy tradeoffs, and time-to-production framework for developer teams.
Normalizing Size Charts Across Brands: From Label to Millimeter
Why 'Size M' means different things across brands, how to build a normalization layer mapping labels to body dimensions, and where the API fits.
The Hidden GDPR Risk in Your Fashion App's Sizing Feature
Photos are biometric data under GDPR Article 9 — requiring explicit legal basis and DPAs. What this means for fashion sizing apps and the stateless alternative.
Sizing Without a Fitting Room: A Technical Playbook for Fashion E-Commerce Teams
Body measurement-based size recommendations for fashion e-commerce — API integration, size chart mapping, and reducing return rates without a fitting room.
Estimating Body Fat Percentage from Circumference Measurements
Validated regression formulas for body fat estimation from circumference measurements — how they work, their limits, and a Python implementation.
Omnichannel Size Recommendation: One Architecture for Web, Mobile, and In-Store
Omnichannel sizing architecture — shared backend for consistent size recommendations across web, mobile, and in-store without divergent logic per channel.
How to Recommend Glasses Frame Sizes Without a Try-On
Build a glasses frame size recommender from head and face dimensions — frame width, bridge fit, temple length, and lens height — from height and weight alone.
Multi-Region Sizing: Why a Single Global Body Model Is Not Enough
Why a single global anthropometric model produces wrong size recommendations for regional markets — the data on population variation and what to do about it.
Predicting Adult Height: Methods for Pediatric Health Applications
Bayley-Pinneau, Khamis-Roche, mid-parental height — three adult height prediction methods explained for developers building pediatric health applications.
Fabric Properties and Sizing Accuracy: What the Body Measurement API Doesn't Know
How fabric stretch, ease allowances, and garment cut affect whether a predicted body measurement actually translates to the right clothing size.
Wearable Device Sizing Without User Friction: A Developer's Approach
Predictive anthropometry for wearable device sizing — smartwatches, hearing aids, and AR glasses sized at onboarding without requiring self-measurement.
Using NLP to Improve Size Recommendations from Customer Reviews
How to extract fit signals from customer reviews for size recommendation — NLP entity extraction, sentiment analysis, and size chart calibration.
Sports Equipment Fit at Scale: From Ski Boots to Bicycle Frames
Using body measurement APIs for sports equipment selection — ski boot flex, bike frame sizing, and protective gear mapping from minimal user input.
Photo-Based vs. Statistical Body Measurement: Which Approach Is Right for Your App?
Photo-based body measurement vs. statistical prediction from height and weight — accuracy, privacy, user friction, and which use cases each approach handles.
Body Measurement APIs in 2026: A Developer's Landscape Guide
The body measurement API landscape in 2026 — categories, use cases, and a practical framework for evaluating which solution fits your technical requirements.
Measurement Form UX: How to Get Users to Enter Their Body Dimensions
Height and weight form UX — field order, unit switching, validation feedback, and the patterns that reduce abandonment when collecting body measurements.
Why Your Clothes Don't Fit: The Science Behind Sizing Inconsistency
Why size 'M' means something different in every brand — the century-old sizing infrastructure behind the chaos, and the science of why clothes don't fit.
Mass Index: An Alternative Body Composition Metric That Accounts for Leg Length
Mass Index (MI) adjusts for trunk-to-leg ratio to produce more accurate body composition estimates than BMI across diverse populations. Algorithm and use cases.
Bergmann's Rule and Why Europeans, Asians, and Africans Need Different Size Charts
The evolutionary biology behind regional body proportion differences — and why a single global sizing model produces statistically invalid recommendations.
Shoe Size Calculator: Foot Measurements and International Size Conversion
Converting foot measurements to shoe sizes across US, EU, UK, and Japanese systems — Mondopoint, width categories, and a complete implementation.
Building an Ergonomic Workstation Calculator from Body Measurement Data
Ergonomic workstation recommendations from body dimensions — desk height, monitor, chair settings, ISO standards, and a complete Python implementation.
International Clothing Size Conversion: US, EU, UK, and Asian Systems
Clothing size conversion across US, EU, UK, and Asian systems — why lookup tables are imprecise and how measurement-anchored conversion works better.
How to Serve Accurate Size Recommendations Across Multiple World Regions
Serve accurate size recommendations to users in the US, Europe, and Asia — map locale or user preference to the right regional body profile in your API calls.
Helmet and Headwear Sizing: From Head Circumference to the Right Size
How head circumference maps to hat and helmet sizes across EU, US, UK, and Japanese systems — with a complete implementation using predicted head circumference.
How to Build a Sports Equipment Size Recommender
Build a multi-sport equipment size recommender — road bike frame sizing, wetsuit fit, ski length, and helmet sizing — from height, weight, and body dimensions.
How to Build a Children's Sizing Feature Without Storing Children's Data
Children's size calculator using the pediatric API — age, height, weight to clothing size — with stateless architecture for GDPR and COPPA compliance.
Building a Children's Size Calculator: Age, Height, and Growth Accommodation
Age-based children's sizing — the age_category API parameter, growth accommodation strategies, and a complete implementation from infant through pre-teen.
Integrating Body Measurement APIs into Shopify and WooCommerce
Size recommendations for Shopify and WooCommerce — server-side proxy, Liquid template integration, WooCommerce PHP hooks, and keeping the API key secure.
How to Build a Size Recommendation Widget in Vanilla JavaScript
Build a complete size recommendation widget in plain JavaScript — server proxy, form, API response parsing, and size chart lookup. No framework required.