CWI Part A vs CWI Part B: how do these CWI parts differ?
Part A tests what you know without a book: terms, processes, symbols, NDE, metallurgy and calculations, in 165 questions over 135 minutes at a Prometric center. Part B tests what you can do: you measure plastic weld replicas with real gauges and judge them against the free Book of Specifications, in 46 questions over 120 minutes. AWS requires Part B first, but both need at least 72%.
CWI Part A vs CWI Part B at a glance
| CWI Part A | CWI Part B | |
|---|---|---|
| Full name | AWS CWI Part A Fundamentals Exam (Certified Welding Inspector) | AWS CWI Part B Practical Exam (Certified Welding Inspector) |
| Questions | 150 scored multiple-choice questions plus 15 unscored pretest items (165 in total) | 46 questions on hands-on tasks with plastic weld replicas, inspection tools and a Book of Exhibits |
| Time | 135 minutes | 120 minutes |
| Passing score | 72% on Part A (each of Parts A, B and C must be passed at 72%) | 72% on Part B (each of Parts A, B and C must be passed at 72%) |
| Format | Closed book, computer-based | Open book: the Part B Book of Specifications (2017) is provided, paper-based |
| Cost | Included in the initial CWI exam fee for all three parts: US$1,255 for AWS members or US$1,520 for non-members (non-member price includes a 3-year AWS membership). A Part A retest costs US$445 | Included in the initial CWI exam fee for all three parts: US$1,255 for AWS members or US$1,520 for non-members (US$2,000 / US$2,265 with Part B training). A Part B retest costs US$385 |
| Languages | English, or language-assisted forms in Chinese, Korean, Japanese, Spanish, Russian and Portuguese (English shown alongside) | English (U.S. customary units in the US and Canada, metric elsewhere); language-assisted forms in several languages, including Chinese, Korean, Japanese, Spanish and Portuguese |
| Where | Prometric test center (computer-based) | AWS-authorized exam sites (paper-based, usually at the end of an AWS seminar week) |
| Level | AWS CWI Exam | AWS CWI Exam |
What each exam covers
CWI Part A
- Definitions, Terminology and Joint Design
- Welding Processes and Cutting
- Welding and NDE Symbols
- Weld Examination and Discontinuities
- WPS, PQR and Welder Qualification
- Nondestructive Testing Methods
- Metallurgy, Heat Control and Destructive Tests
- Calculations, Duties and Safety
CWI Part B
- Inspection Tools and Dimensional Tolerances
- Structural Steel Acceptance Criteria
- Pipeline Acceptance Criteria
- Pressure Piping Acceptance Criteria
- WPS and PQR Review
- Welder Performance Qualification
- Mechanical Tests and NDE Exhibits
Which should you take?
Part A tests what you know without a book: terms, processes, symbols, NDE, metallurgy and calculations, in 165 questions over 135 minutes at a Prometric center. Part B tests what you can do: you measure plastic weld replicas with real gauges and judge them against the free Book of Specifications, in 46 questions over 120 minutes. AWS requires Part B first, but both need at least 72%.
Try both, free
Each free practice test takes about 10 minutes and shows your score by topic. No signup.
FAQ
What is the difference between CWI Part A and CWI Part B?
Part A tests what you know without a book: terms, processes, symbols, NDE, metallurgy and calculations, in 165 questions over 135 minutes at a Prometric center. Part B tests what you can do: you measure plastic weld replicas with real gauges and judge them against the free Book of Specifications, in 46 questions over 120 minutes. AWS requires Part B first, but both need at least 72%.
Which is harder, CWI Part A or CWI Part B?
CWI Part A: 150 scored multiple-choice questions plus 15 unscored pretest items (165 in total) in 135 minutes. CWI Part B: 46 questions on hands-on tasks with plastic weld replicas, inspection tools and a book of exhibits in 120 minutes. The longer exam covers more ground, but the harder one is the one further from your daily work. Take both free practice tests to see where you stand.
Can I hold both CWI Part A and CWI Part B?
You need all three parts to earn the CWI: Part A, Part B and Part C, each at 72% or better.
How do I prepare for CWI Part A and CWI Part B?
Start with the free practice test for each, then study by topic. Premium is per exam ($147 a month each), so most people start with the exam they'll sit first and add the second when they're ready.
More comparisons
Exam details are summarized from AWS's published information as of October 2026. Confirm with AWS before you book. CWIQuizBank is not affiliated with the American Welding Society or Prometric.