| Upper Material |
Confirm the exact fiber, coating, thickness, finish, and backing used in the upper. |
Material specifications should match the approved sample and purchase specification. |
Review the technical data sheet, compare color and texture under consistent lighting, and request a pre-production sample. |
Unspecified “synthetic leather,” inconsistent grain, strong chemical odor, or visible surface cracking during bending. |
| Leather Quality |
For leather uppers, assess grain type, thickness, softness, dye uniformity, and surface defects. |
Thickness and finish should remain consistent across the approved production tolerance. |
Check a cross-section, perform repeated flexing, and inspect for loose grain, scars, peeling finish, and uneven dye penetration. |
Heavy surface correction hiding defects, patchy color, loose grain, or finish transfer onto a white cloth. |
| Textile or Knit Upper |
Evaluate yarn composition, knit density, abrasion resistance, stretch recovery, and colorfastness. |
The upper should retain its shape after repeated stretching and show no excessive yarn pull-out. |
Perform seam-area inspection, dry and wet rubbing checks, stretch-recovery checks, and abrasion testing through an accredited laboratory when required. |
Uneven knit tension, exposed yarn ends, excessive pilling, color bleeding, or permanent deformation. |
| Lining and Insole |
Check lining comfort, moisture management, odor, abrasion resistance, and insole dimensional stability. |
Materials should not cause sharp edges, excessive friction, color transfer, or early collapse under normal wear. |
Inspect internal seams by hand, conduct rubbing and sweat-contact checks, and compare insole compression before and after wear simulation. |
Rough seam allowances, loose lining, adhesive exposed inside the shoe, or insole compression that creates a noticeable height difference. |
| Outsole Compound |
Identify the outsole material, hardness, tread design, flex pattern, and resistance to wear and slipping. |
Hardness and compound should be consistent between pairs; tread should remain defined after wear testing. |
Verify material documentation, measure hardness with a suitable durometer, inspect molding, and conduct abrasion and slip-resistance tests appropriate to the end use. |
Air bubbles, incomplete molding, sharp flashing, uneven tread depth, or a compound that becomes brittle after flexing. |
| Midsole and Cushioning |
Evaluate foam density, rebound, compression set, stability, and bonding to the upper and outsole. |
Left and right shoes should provide similar cushioning and return to shape after repeated compression. |
Check density records, perform repeated compression checks, and inspect for permanent deformation after wear simulation. |
Visible foam voids, uneven hardness, early bottoming-out, squeaking, or separation at the midsole edge. |
| Last and Fit |
Confirm length, width, toe shape, heel hold, instep volume, and size grading. |
Measurements should follow the approved last and agreed size chart, with consistent left-right symmetry. |
Measure finished shoes with a standardized footwear measuring device and conduct fit trials on representative foot shapes. |
Toe pressure, heel slippage, inconsistent width between sizes, asymmetric toplines, or a fit that changes substantially between pairs. |
| Stitching |
Inspect stitch density, thread tension, seam allowance, back-tacking, and alignment at high-stress areas. |
Stitches should be even, secure, and free from skipped stitches, loose threads, and broken thread ends. |
Use visual inspection, measure stitch spacing against the approved specification, and pull-test critical seams when applicable. |
Skipped stitches, puckering, uneven seam lines, loose thread tails, or stitching placed too close to the material edge. |
| Bonding and Adhesives |
Check adhesive coverage, curing, bond-line cleanliness, and compatibility between upper, midsole, and outsole materials. |
No visible opening should occur during flexing, peeling, or normal wear simulation. |
Inspect the bond line, flex the shoe repeatedly, and use peel or sole-adhesion testing based on the applicable footwear test method. |
Glue overflow, unbonded corners, whitening, bubbling, weak toe or heel adhesion, and separation after flexing. |
| Toe and Heel Structure |
Assess reinforcement placement, shape retention, counter stiffness, and protection from collapse. |
The toe box and heel counter should maintain the approved shape without sharp or uncomfortable edges. |
Compare against the approved sample, apply repeated compression, and inspect internal reinforcement placement. |
Wrinkling, distorted toe shape, collapsed heel counter, exposed reinforcement, or inconsistent structure between shoes. |
| Flexing Performance |
Evaluate how the shoe bends at the intended flex point and whether materials crack, crease, or separate. |
The shoe should flex smoothly without visible cracking, delamination, or stitch failure. |
Use a controlled flex test suitable for the shoe category and inspect the upper, outsole, seams, and bond lines afterward. |
Flexing at the wrong location, deep permanent creasing, surface cracks, sole splitting, or upper-to-sole separation. |
| Colorfastness |
Check resistance to rubbing, perspiration, water, and light exposure according to the product’s intended use. |
Color transfer should remain within the limit specified for the target market and test method. |
Request dry and wet crocking results, compare production material with the approved color standard, and review laboratory reports. |
Color transfer to socks, uneven shade between components, rapid fading, or different color lots within one pair. |
| Dimensional Consistency |
Measure pair symmetry, outsole length, ball width, opening circumference, and component placement. |
Finished dimensions should remain within documented tolerances for each size. |
Use a sampling plan, calibrated measuring tools, and a signed measurement sheet for every production lot. |
Left-right mismatch, inconsistent size grading, crooked logos or trims, and visibly different toe or heel heights. |
| Safety and Restricted Substances |
Review materials, dyes, adhesives, metal parts, packaging, and country-specific chemical requirements. |
Testing should meet the legal and retailer requirements of the destination market before shipment. |
Use an independent laboratory and provide traceable reports tied to the actual production materials and colorways. |
Outdated reports, reports for a different material or color, missing test scope, or undocumented material substitutions. |
| Factory Process Control |
Assess incoming-material inspection, cutting, stitching, lasting, bonding, finishing, and final inspection procedures. |
Critical processes should have documented work instructions, checkpoints, and corrective-action records. |
Conduct a factory audit, review quality-control records, observe a production line, and verify operator inspection points. |
Reliance on final inspection only, undocumented rework, uncontrolled material substitutions, or no lot traceability. |
| Sampling and Acceptance |
Define critical, major, and minor defects before production and establish a consistent inspection approach. |
Use a documented sampling plan such as an agreed AQL system, with zero tolerance for critical safety defects. |
Perform pre-production, during-production, and pre-shipment inspections using the same approved checklist. |
Changing defect definitions after production, inspecting only the best cartons, or accepting repeated major defects without corrective action. |
| Packaging and Traceability |
Verify carton strength, pair labeling, size identification, moisture protection, and production-lot traceability. |
Every pair and carton should be identifiable by style, size, color, production lot, and inspection status. |
Perform carton-drop or transport checks when required and reconcile packing lists with physical quantities. |
Mixed sizes, missing labels, crushed cartons, inadequate moisture protection, or no link between cartons and production records. |
