---
title: "CNC Practical Test Examples for a Job Interview (With Answers)"
description: "Sample CNC interview questions with answers: read this block, what does M03 do, G02 vs G03, and units. Practice these and the test feels familiar."
url: https://gcodepractice.com/journal/cnc-practical-test-examples-for-job-interview/
canonical: https://gcodepractice.com/journal/cnc-practical-test-examples-for-job-interview/
author: "Lawrence Arya"
authorUrl: https://www.linkedin.com/in/vibecoding/
published: 2026-06-02
updated: 2026-06-02
category: "Practice"
tags: ["interview", "test prep", "examples", "beginner"]
lang: en
---

# CNC Practical Test Examples for a Job Interview (With Answers)

> **TL;DR** A CNC practical test for an interview usually mixes short program reading with direct code recall: what a block does, what M03 and M05 do, the difference between G02 and G03, and which units or positioning mode is active. The answers come from the common G-code and M-code, so drilling those for recall is the fastest prep.

Lists of topics are easy to nod along to and hard to actually use. Worked examples are better, because they show you the exact shape of the questions. Here are realistic ones with the answers.

## Sample questions and answers

- **"What does `G01 X50 F150` do?"** A straight-line feed move to X50 at a feedrate of 150 units per minute. It is a cutting move.
- **"What is the difference between `G00` and `G01`?"** `G00` is a rapid (fast, non-cutting positioning); `G01` is a controlled feed move that cuts. See [G00 vs G01](/journal/g00-vs-g01/).
- **"What does `M03` do, and `M05`?"** `M03` starts the spindle clockwise; `M05` stops it.
- **"`G02` or `G03` for a counterclockwise arc?"** `G03`. `G02` is clockwise. See [G02 vs G03](/journal/g02-vs-g03/).
- **"How do you know if a program is in inches or millimeters?"** Look for `G20` (inch) or `G21` (millimeters).
- **"What does `G90` mean?"** Absolute positioning: coordinates are measured from part zero.

## Quick-reference answers

| Question | Answer |
| --- | --- |
| `G00` vs `G01` | Rapid (no cut) vs linear feed (cut) |
| `M03` / `M05` | Spindle on clockwise / spindle stop |
| Counterclockwise arc | `G03` (`G02` is clockwise) |
| Inch vs metric | `G20` (inch) / `G21` (mm) |
| `G90` | Absolute positioning from part zero |
| `G91` | Incremental positioning from current point |

## How to practice

Every answer above is recall of a common code, so the prep is recall practice, not re-reading. Drill the [common G-codes](/journal/common-g-codes-for-cnc-beginners/) and [common M-codes](/journal/common-m-codes-for-cnc-beginners/) both directions, put extra reps on the mix-ups, and rehearse under a timer so the answers come fast. That is the method in [beginner CNC code practice](/journal/beginner-cnc-code-practice/), and the timed mode in [G-Code Sprint](/g-code-practice/) mirrors the pressure of being asked out loud. For the broader interview, see [the G-code test for a job interview](/journal/g-code-test-for-job-interview/).

## Bottom line

CNC practical tests mix short program reading with direct code recall. Practice the exact question types as recall drills, with a timer, and the interview becomes a review rather than a surprise.

## Sources

- [NIMS (National Institute for Metalworking Skills)](https://www.nims-skills.org/)
- [LinuxCNC G-code quick reference](https://linuxcnc.org/docs/html/gcode/g-code.html)
- [CNCCookbook: G-code and M-code cheat sheet](https://www.cnccookbook.com/g-code-m-code-cnc-list-cheat-sheet/)

## Frequently asked questions

### What kind of questions are on a CNC practical test?
A mix of reading a short program, identifying what individual codes do, and the common comparisons like `G00` vs `G01` or `G02` vs `G03`. Some also include basic measurement and safety questions.

### Do CNC interviews ask you to write G-code?
Entry-level interviews usually ask you to read and explain code more than write it from scratch. They want to see you understand what a program does and can spot the common codes confidently.

### What is the best way to practice CNC interview questions?
Turn the question types into recall drills. A free tool like G-Code Sprint quizzes code-to-meaning, meaning-to-code, and the common mix-ups, with a timed mode that mirrors interview pressure.

*G-Code Sprint is a study and practice tool only. Always follow your instructor, employer, machine manual, and shop safety procedures.*

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Source: https://gcodepractice.com/journal/cnc-practical-test-examples-for-job-interview/
Author: Lawrence Arya — https://www.linkedin.com/in/vibecoding/