Comparison

CWI Welding Exam Prep vs NDT Cert Study

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

CWI Welding Exam Prep

Prepare for all three parts of the AWS CWI exam with this comprehensive study tool. Features include a weld symbol decoder, discontinuity reference, and over 490 practice questions covering fundamentals, practical inspection, and code book navigation. Access a free overview and daily questions.

Highlights
  • Three-part exam preparation (Fundamentals, Practical, Code Book)
  • Weld symbol decoder based on AWS A2.4
  • Discontinuity reference with causes and acceptance criteria
  • 490+ practice questions
  • Covers welding processes, metallurgy, NDT, and safety
  • Code navigation assistance
Features
Read full description

CWI WELDING EXAM PREP: PASS ALL THREE PARTS OF THE AWS CWI EXAM The CWI exam has a 30 percent first-attempt pass rate. Most candidates fail because they treat it as a single test. It is three separate exams — Part A (Fundamentals), Part B (Practical), and Part C (Code Book) — each requiring different preparation. This app is built around all three. WELD SYMBOL DECODER Weld symbols are tested heavily on Part A and appear throughout Part C. This tool lets you build any symbol and get an instant plain-English interpretation based on AWS A2.4. Select your weld type: fillet, groove (V, bevel, U, J, square), plug, slot, spot, seam, surfacing. Choose position: arrow side, other side, both sides. Add supplementary symbols: field weld, weld all around, melt-through. Set contour and finishing requirements. Get the decoded meaning instantly. The same symbols you will interpret on blueprints every day on the job. Source: AWS A2.4 Standard Symbols for Welding, Brazing, and Nondestructive Examination — https://www.aws.org/standards DISCONTINUITY REFERENCE Identifying and classifying weld discontinuities is the core of Part B. This reference covers every discontinuity type. Covered: porosity, slag inclusion, incomplete fusion, incomplete joint penetration, undercut, overlap, cracks (longitudinal, transverse, crater), arc strikes, underfill, laminations. For each: visual description, probable causes, prevention, and AWS D1.1 acceptance criteria for both prequalified and qualified welds. Source: AWS D1.1 Structural Welding Code — https://www.aws.org/standards 490+ PRACTICE QUESTIONS Part A — Fundamentals (150 questions on actual exam): Welding processes: SMAW, GMAW, GTAW, FCAW, SAW — parameters, applications, limitations. Welding metallurgy: heat-affected zones, preheat, interpass temperature, post-weld heat treatment. Weld symbols: AWS A2.4 interpretation, construction, and supplementary symbols. Welding terminology: AWS A3.0 standard terms and definitions. NDT methods: VT, PT, MT, RT, UT — capabilities, limitations, applications. Welding safety: fire watch, PPE, fumes, electrical hazards, confined space. Part B — Practical (50 questions on actual exam): Visual inspection procedure and sequence. Discontinuity identification from descriptions and specifications. Measurement: fillet weld gauges, undercut depth, reinforcement, throat. Acceptance criteria application: when to accept, when to reject. Part C — Code Book (50 questions on actual exam): AWS D1.1 Structural Welding Code: general requirements, design, prequalification, qualification, fabrication, inspection. WPS (Welding Procedure Specification): required variables, essential variables, format. PQR (Procedure Qualification Record): test required, acceptance, documentation. Welder qualification: positions, test weld types, retesting requirements. Code navigation: finding the right clause under exam time pressure. FREE: 5 questions per day, symbol type reference, Part A overview. No account required. MONTHLY ($9.99/month): Full 490+ question bank, complete Weld Symbol Decoder, Discontinuity Reference, D1.1 Code Navigator, progress tracking by exam part, 3-day free trial. ANNUAL ($24.99/year): Everything in Monthly. Save over 75 percent. Best value. LIFETIME ($49.99): One payment. Permanent access. PASS PROMISE: Complete all questions with 80% or higher average, hold active subscription for 3 months, still do not pass. We extend your access by 4 months at no charge. voltexam.com/pass-promise AWS, CWI, and AWS D1.1 are trademarks of the American Welding Society. Not affiliated with or endorsed by AWS. Privacy Policy: https://www.voltexam.com/privacy Terms of Service: https://www.voltexam.com/terms

About

NDT Cert Study

Features
Read full description

NDT Cert Study is a practice-question app for anyone preparing for nondestructive testing certification exams. It covers the main methods and code references: • Ultrasonic (UT) Levels I and II, plus phased array (PAUT) • Penetrant (PT) Levels I and II • Magnetic particle (MT) Levels I and II • Radiographic (RT) Levels I and II • API 1104 weld acceptance-criteria questions integrated into the UT and RT tracks Each question includes a worked explanation, so you learn why an answer is right, not just which one. The app tracks how ready you are by topic, lets you save tricky questions for another pass, and includes timed practice exams. Everything works offline. Your progress stays on your device. Modules unlock with a single one-time purchase. No subscription. NDT Cert Study is an independent study aid. It is not affiliated with, endorsed by, or sponsored by API, ASNT, ISO, CGSB, BINDT/PCN, or TWI/CSWIP. All certification names and marks are the property of their respective owners.

Screenshots

CWI Welding Exam Prep4 screens
NDT Cert Study4 screens

Verdict

The call

The clearest difference is device support: NDT Cert Study at 3 against CWI Welding Exam Prep's 1. NDT Cert Study also leads on iOS requirement (15.1 vs 17.0). On price, update cadence, ads and in-app purchases there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. CWI Welding Exam Prep sells 3 in-app purchases, starting at $9.99 per month and NDT Cert Study sells 10 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly every 3 weeks. The most recent releases landed on October 24, 2026 and October 25, 2026 respectively.

Scorecard2 real differences · 7 level
CWI Welding Exam Prep versus NDT Cert Study: the parameters behind the verdict, then further details
ParameterCWI Welding Exam PrepNDT Cert Study
PriceFreeFree
Rating4.4 (14 ratings) — better—
Number of ratings14 — better—
Update frequencyEvery 3 weeksEvery 3 weeks
AdsNoNo
In-app purchasesYesYes
MonetizationFreemium—
DevicesiPhoneiPhone, iPad, iPod — better
Requires iOS17.015.1 — better
Further details — not scored
Size6 MB35 MB
Age rating4+4+
DeveloperDeeun Inc.Simon Shih

In-app purchases

3 purchases

CWI Welding Exam Prep

Subscriptions2
  • Monthly Access3 Days trial$9.991 Month
  • Annual Access$24.991 Year
One-time1
  • CWI Prep - Lifetime Pro$49.99
10 purchases

NDT Cert Study

One-time10
  • CGSB / MT Level II$9.99
  • CGSB / MT Level I$9.99
  • CGSB / RT Level I$9.99
Show 7 more
  • CGSB / PT Level II$9.99
  • CGSB / PT Level I$9.99
  • CGSB / RT Level II$9.99
  • CGSB / UT Level II$9.99
  • CGSB / UT Level I$9.99
  • CGSB / PAUT Level I$9.99
  • CGSB / PAUT Level II$9.99

Questions

Is CWI Welding Exam Prep free?
CWI Welding Exam Prep is free to download, with in-app purchases available.
Is NDT Cert Study free?
NDT Cert Study is free to download, with in-app purchases available.
Do CWI Welding Exam Prep or NDT Cert Study have ads?
Neither CWI Welding Exam Prep nor NDT Cert Study shows ads.
Which is updated more often, CWI Welding Exam Prep or NDT Cert Study?
CWI Welding Exam Prep ships an update every 3 weeks, and NDT Cert Study every 3 weeks. Most recently, CWI Welding Exam Prep was updated on October 24, 2026 and NDT Cert Study on October 25, 2026.

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