GD&T Study Guide 2026

Everything you need to pass the GD&T exam in one place: the exam format, every topic to study, real practice questions with explanations, flashcards, and full-length practice tests. Free, no sign-up needed.

📋 GD&T Exam Format at a Glance

150

Questions

240 min

Time Limit

78%

Passing Score

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📚 GD&T Topics to Study (69)

Datum Systems & Reference Frames · 9 cards Geometric Symbols & Notation · 9 cards Surface Finish & Assembly Requirements · 9 cards Tolerances & Fits in Engineering Drawings · 9 cards Composite Feature Control · 7 cards Composite Feature Control · 7 cards Composite Feature Control · 7 cards Composite Feature Control · 7 cards Datum Reference Frames · 7 cards Datum Reference Frames · 7 cards Datum Reference Frames · 7 cards Datum Reference Frames · 7 cards Datum Systems & Reference Frames · 7 cards Datum Systems & Reference Frames · 7 cards Datum Systems & Reference Frames · 7 cards Datum Systems & Reference Frames · 7 cards Form and Orientation Tolerances · 7 cards Form and Orientation Tolerances · 7 cards Form and Orientation Tolerances · 7 cards Form and Orientation Tolerances · 7 cards Geometric Symbols & Notation · 7 cards Geometric Symbols & Notation · 7 cards Geometric Symbols & Notation · 7 cards Geometric Symbols & Notation · 7 cards Material Condition Modifiers · 7 cards Material Condition Modifiers · 7 cards Material Condition Modifiers · 7 cards Material Condition Modifiers · 7 cards Position Tolerancing Calculations · 7 cards Position Tolerancing Calculations · 7 cards

See all 69 topics as flashcards →

✍️ Sample GD&T Questions & Answers

1. What is the purpose of using multiple datum targets (e.g., A1, A2, A3) to establish a single datum plane?

✓ To simulate a datum plane on a non-flat or flexible surface using discrete contact points

Multiple datum targets simulate a plane on irregular surfaces (like castings) by defining exact contact points rather than relying on full surface contact.

2. A component drawing requires a surface finish of Ra 0.8 μm on a mating face. The manufacturing engineer proposes lapping instead of grinding. This is acceptable if:

✓ Lapping can achieve Ra 0.8 μm and no process restriction is noted

Without a specified process restriction on the surface symbol, any process that achieves the required Ra value is acceptable per drawing intent.

3. What is the role of surface texture in GD&T?

✓ To ensure proper contact between parts.

Surface texture, including roughness, waviness, and lay, plays a critical role in GD&T by influencing how mating parts interact. It affects friction, wear, lubrication, sealing, and electrical contact. Specifying appropriate surface texture ensures proper functional contact, prevents premature failure, and achieves desired performance characteristics.

4. A drawing note states 'ALL TOLERANCES ±0.005 UNLESS OTHERWISE SPECIFIED.' A dimension shown as 3.750 +0.010/−0.000 would have which tolerance applied?

✓ +0.010/−0.000 as shown on the dimension

A specific tolerance shown on a dimension always overrides the general title block tolerance for that particular feature.

5. Which symbol designates a datum target area in GD&T?

✓ A circle divided by a horizontal line with the target ID

A datum target symbol is a circle divided by a horizontal line; the lower half contains the datum letter and target number (e.g., A1).

6. An MMC modifier is applied to the FRTZF of a composite position callout. What benefit does this provide?

✓ It provides bonus tolerance for feature-to-feature location as features depart from MMC

An MMC modifier on the FRTZF allows each feature's tolerance zone to increase (bonus tolerance) as the feature departs from MMC, while still maintaining pattern geometry.

🎯 Free GD&T Practice Tests

Surface Finish & Assembly Requirements · 9 questions Datum Systems & Reference Frames · 9 questions Tolerances & Fits in Engineering Drawings · 9 questions Geometric Symbols & Notation · 9 questions Symbols and Rules · 7 questions Symbols and Rules · 7 questions Surface Finish & Assembly Requirements · 7 questions Surface Finish & Assembly Requirements · 7 questions Symbols and Rules · 7 questions Symbols and Rules · 7 questions

📖 GD&T Guides & Articles

Your GD&T Study Path

1. Learn with Flashcards → 2. Drill Practice Tests → 3. Take the Full Exam Simulation

🃏 GD&T Flashcards (477)🏆 GD&T Exam Simulation

What Practice Test Geeks adds beyond an AI chat for GD&T

An AI chatbot can quiz you, but it can't reproduce the exam conditions or keep your record. Here you get:

A timed, full-length GD&T mock exam — 150 questions in 240 minutes with a 78% pass mark, modeled on the official exam's question count and time limit, followed by a score report broken down by exam domain.
A fixed GD&T question bank: the same test every attempt, so your score is comparable from one try to the next instead of changing with every regenerated quiz.
Progress saved on your device: completed tests, scores and missed questions stay in My Progress, so you can retake only what you got wrong.
A printable GD&T cheat sheet you can print or save as a PDF.
GD&T flashcards built from the same question bank.
Free GD&T practice tests with the correct answer shown after each question.

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