In-Production vs Pre-Shipment Inspection
Two types of quality inspections protect your China sourcing orders — but they serve different purposes. This guide explains what each inspection covers, when to use them, and which combination is right for your situation.
Short answer
An in-production inspection (DUPRO) checks quality at 20–40% completion to catch defects early. A pre-shipment inspection (PSI) checks finished products using AQL sampling before shipping. Use both for new suppliers and large orders; PSI alone is sufficient for repeat suppliers with proven quality.
Side-by-Side Comparison
| Aspect | In-Production (DUPRO) | Pre-Shipment (PSI) |
|---|---|---|
| When it happens | At 20–40% production completion | After 100% production, before shipping |
| Primary purpose | Catch defects early, correct in real-time | Confirm final quality before shipment |
| What is checked | Materials, assembly process, early output | Finished products (AQL sampling) |
| Sample size | Random pull from completed units | AQL-based statistical sampling |
| Defects found | Systematic issues — wrong materials, process errors | Cosmetic, functional, packaging issues |
| Corrective action | Factory corrects before remaining 60–80% is made | Rework, reject batch, or accept with conditions |
| Cost of failure | Low — only 20–40% of production affected | High — entire batch may need rework or rejection |
| Best for | New suppliers, complex products, large orders | Repeat suppliers, standard products, every shipment |
| Typical cost | $250–$400 per inspection | $200–$350 per inspection |
In-Production Inspection (DUPRO) — What We Check
The DUPRO inspection happens when roughly one-third of production is complete. This timing is critical — it is early enough to correct issues without wasting the entire batch, but late enough to see actual production output and identify systematic problems.
Raw materials match approved specifications and samples
Production process follows agreed manufacturing procedures
Early-stage output matches quality standards and dimensions
Assembly accuracy and component alignment
Colour consistency across production run
Packaging materials prepared and correct
Production timeline on track to meet delivery deadline
Pre-Shipment Inspection (PSI) — What We Check
The PSI is your last line of defence before products leave China. Using AQL statistical sampling, we inspect a random selection of finished units to determine whether the entire batch meets your quality standards.
AQL sampling — random selection based on order quantity
Visual inspection for cosmetic defects (scratches, dents, colour variation)
Functional testing — product operates as specified
Dimensional accuracy against approved drawings/samples
Packaging integrity — correct labels, barcodes, inserts, box quality
Carton drop test and weight verification
Compliance markings present (CE, FCC, UL, etc.) where required
Quantity verification against purchase order
Which Inspection Do You Need?
New Supplier, First Order
→ Both DUPRO + PSI
You have no track record with this factory. DUPRO catches systemic issues early; PSI confirms the final output meets your standards.
Repeat Supplier, Standard Product
→ PSI only
You know this factory delivers consistent quality. A pre-shipment inspection confirms each batch before shipping.
Complex or Custom Product
→ Both DUPRO + PSI
Custom products have more variables that can go wrong. Catching issues at 30% completion saves significantly more than discovering them at 100%.
Large Order (5,000+ units)
→ Both DUPRO + PSI
The financial risk of a defective large batch justifies the cost of two inspections. DUPRO at 30% prevents 70% of production from being affected.
Small Order (<500 units)
→ PSI only
For smaller orders, the cost of two inspections may not be justified. A thorough PSI before shipment provides adequate quality assurance.
Amazon FBA Shipment
→ PSI + FBA compliance check
Amazon rejects non-compliant shipments. PSI should include FNSKU label verification, poly-bag checks and carton prep review.
The Cost of Skipping Inspections
Skipping inspections to save $200–$400 is one of the most expensive mistakes in China sourcing. Without inspections, defective products reach your warehouse — or worse, your customers. The consequences include:
Customer returns and refunds — typically 5–15x the inspection cost
Negative reviews that damage your brand and sales rankings
Amazon account health warnings or suspension for FBA sellers
Customs rejection or hold for non-compliant products
Cost of re-ordering or reworking an entire production batch
Lost time — 2–4 months to re-source, re-produce and re-ship
Learn more about our quality inspection services or read our guide on how to verify Chinese suppliers.