Study Guide

CWI exam guide: Build a practical three-part study plan

Prepare for AWS CWI with the three tested parts, a complete criterion-comparison exercise, current reference rules and an adaptable study checklist.

Updated September 20266 min readStudy GuideWelding Exam
Elizabeth Wright

Elizabeth Wright

Welding Exam Editorial Team

Prepare for the American Welding Society Certified Welding Inspector (CWI) exams with a separate task list for fundamentals, practical inspection and code application. Use the topic map, solve the measurement exercise, and check which reference and format your selected Part C exam uses.

Who can apply for CWI?

The usual eligibility route is a high school diploma or equivalent plus five years of qualifying welding-based work experience. Submit the required education, experience and visual-acuity documentation.

AWS B5.1:2025 also describes other education and experience combinations. Relevant approved education can reduce the work requirement, but credit is limited and does not remove it. Check the table and supporting-document requirements for your own background rather than assuming any degree qualifies.

CWI is the American Welding Society welding inspector credential. Your construction or piping background does not create a different CWI syllabus, and a preparation course does not replace the eligibility requirements.

Sources: Certified Welding Inspector (CWI) | AWS Certification Program — AWS CWI program page; Examination User Guide for CWI, September 4, 2026 — AWS CWI Examination User Guide (PDF); AWS B5.1:2025 – Specification for the Qualification of Welding Inspectors — Clauses 6–8

What should you expect in Parts A, B and C?

CWI requires at least 72% on each of the three parts. A high result on one part does not compensate for a result below that threshold on another.

Take Part B before Parts A and C. Part B is a practical inspection examination using supplied specimens and documents; you do not produce a live weld. Confirm the selected Part C form and its timing when you book.

PartFormat and questionsQuestion time
A: FundamentalsClosed-book computer test at Prometric; 165 total, including 150 scored and 15 unscored pretest items135 minutes
B: PracticalPaper examination at an AWS-authorized site using supplied inspection materials; 46 questions120 minutes
C: CodebookOpen-book computer test at Prometric; 50–60 scored, with 55–65 total on English forms containing pretest items135 minutes with pretest items; 120 without

Sources: Examination User Guide for CWI, September 4, 2026 — AWS CWI Examination User Guide (PDF); CWI Part A Fundamentals Examination Information Guide (Rev. 03.01.2024) — AWS Part A exam information (PDF); CWI Part B Practical Examination Information Guide (Rev. 03.01.2024) — AWS Part B exam information (PDF); CWI Part C Codebook Applications Examination Information Guide (Rev. 02.11.2025) — AWS Part C exam information (PDF)

What should you practise for each part?

Build a separate task list for fundamentals, practical inspection and code application. Use the current official content guides to check coverage.

The table summarizes the tested areas and suggests study tasks. NDE means nondestructive examination. Review the methods and their limitations using appropriate technical references; the study tasks do not replace the full content guides.

PartAreas to reviewA useful study task
ATerminology; welding and cutting processes; symbols; weld examination; welding application and control; NDE; heat control and metallurgy; calculations; inspector duties; destructive tests; safetyExplain a concept, interpret a symbol or work a calculation, then check the reasoning against an appropriate reference.
BInspection and discontinuity evaluation; procedure and welder qualification; mechanical tests and properties; NDE; specifications and drawingsUse the supplied practice specification and exhibits to identify the applicable criterion, units, evidence and decision.
CQualification; fabrication; inspection; reports and records; materials and designLocate an applicable requirement and its exceptions in the approved reference for your chosen exam, then explain its application.

Sources: CWI Part A Fundamentals Examination Information Guide (Rev. 03.01.2024) — AWS Part A exam information (PDF); CWI Part B Practical Examination Information Guide (Rev. 03.01.2024) — AWS Part B exam information (PDF); CWI Part C Codebook Applications Examination Information Guide (Rev. 02.11.2025) — AWS Part C exam information (PDF)

Which study materials and codebook do you need?

Match materials to the exam part: fundamentals references for A, the public sample Book of Specifications for B, and the approved reference and edition for your selected Part C exam.

The Part A guide points to informative references for self-education rather than prescribing one study book. For Part B, practise with the public sample Book of Specifications and read the exam content guide. The exam provides its inspection materials, including exhibits, plastic replicas and an inspection tool kit.

Before buying a Part C reference, check the current Exam References and Editions Guide. For example, its D1.1 entry permits the 2020 or 2025 edition. Do not assume the newest edition of every other code is the one specified for your exam.

Some Part C exams provide an on-screen PDF and prohibit printed codebooks. Where paper is permitted, use an original publication or permanently bound printed copy with securely attached pages and bound errata. Check your selected exam’s rules and practise navigating the reference format it uses.

Sources: Examination User Guide for CWI, September 4, 2026 — AWS CWI Examination User Guide (PDF); CWI Part A Fundamentals Examination Information Guide (Rev. 03.01.2024) — AWS Part A exam information (PDF); CWI Part B Practical Examination Information Guide (Rev. 03.01.2024) — AWS Part B exam information (PDF); CWI Part C Codebook Applications Examination Information Guide (Rev. 02.11.2025) — AWS Part C exam information (PDF); AWS Exam References and Editions Guide (last updated August 1, 2025) — AWS open-book exam reference guide (PDF)

Practise comparing a value with a written criterion

An inspection note for this exercise should make the comparison traceable: record the supplied value, its units, the criterion and the result.

Work this original paper exercise before reading the answer. The criterion is invented for training and does not supply an AWS or governing-code limit.

Practice exercise

For this fictional paper exercise only, criterion T-7 permits a bead height from 5.5 mm through 6.5 mm, inclusive. Treat the supplied measurements as exact: specimen A = 5.4 mm, specimen B = 6.0 mm and specimen C = 6.5 mm. For each specimen, state whether it meets T-7 and what you would record in a study inspection note.

Show answer

Specimen A (5.4 mm) fails T-7, because 5.4 mm is below the 5.5 mm minimum. Specimen B (6.0 mm) meets T-7, because it falls inside the 5.5–6.5 mm range. Specimen C (6.5 mm) also meets T-7, because the criterion says "inclusive," so a value exactly on the 6.5 mm upper limit is acceptable. For each specimen, an inspection note would record: the measured value with units, the criterion reference (T-7), the comparison made, and the resulting disposition.

A falls below the lower limit, B is within the range and C equals the included upper limit. Inclusive wording makes that endpoint acceptable under T-7. Keep each result linked to the value and criterion used. The exercise establishes only whether the supplied measurements meet this invented requirement; a complete weld-acceptance decision needs all applicable criteria and evidence.

Sources: CWI Part B Practical Examination Information Guide (Rev. 03.01.2024) — AWS Part B exam information (PDF)

How can you turn practice errors into a study plan?

Record the specific reason for each missed or guessed answer, then choose a short follow-up task that addresses it.

  • Concept gap: revisit the relevant Part A topic and explain it in your own words.
  • Reference gap: practise finding the applicable provision and exceptions in the correct Part B or C document.
  • Calculation or interpretation gap: write the units, limits and comparison before deciding whether a supplied value meets the stated criterion.
  • Timing gap: repeat a short set under timed conditions after you understand the answers.
  • Coverage gap: compare your error log with all three content guides; repeated practice in one familiar area does not cover the other parts.

Sources: CWI Part A Fundamentals Examination Information Guide (Rev. 03.01.2024) — AWS Part A exam information (PDF); CWI Part B Practical Examination Information Guide (Rev. 03.01.2024) — AWS Part B exam information (PDF); CWI Part C Codebook Applications Examination Information Guide (Rev. 02.11.2025) — AWS Part C exam information (PDF)

What should you check before applying?

Candidates in the US and Canada apply through AWS; candidates outside that area use an AWS Agent. Confirm the current application route, total price and required documents for your location.

Use the confirmation letter and eligibility codes to arrange the computer-based parts, and keep the required order of taking Part B first. Check appointment instructions for identification, arrival, permitted equipment and rescheduling.

CWI renewal falls at years three and six, followed by nine-year recertification. Review the current requirements and available recertification routes as your deadline approaches.

Sources: Certified Welding Inspector (CWI) | AWS Certification Program — AWS CWI program page; Examination User Guide for CWI, September 4, 2026 — AWS CWI Examination User Guide (PDF)

Sources

Facts checked:

Next steps

FAQ

Frequently Asked Questions

Practical answers to help you apply the guidance for Certified Welding Inspector (CWI).

Does a practice-test percentage guarantee I will pass CWI?
No. Use practice results to identify gaps in the current content guides and review the reasoning behind missed or guessed answers. The official CWI standard is at least 72% on each exam part; a separate practice set does not establish that result.
Is an AWS seminar mandatory for an initial application?
No. AWS training is optional for the initial CWI exam. Eligibility documentation remains necessary, and later retests can have additional training requirements under the current user guide.

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