If you’ve led a process improvement effort, sat on a DMAIC team, or used data to fix a recurring problem at work, the Certified Six Sigma Green Belt (CSSGB) from ASQ (formerly the American Society for Quality) lets you prove you can do it with rigor. The exam covers a lot of ground, from project charters to control charts, and the statistics can feel intimidating at first. The good news is that ASQ publishes exactly what it tests, and a study plan built around that blueprint makes the exam very passable on your first try.

In this guide, we’ll walk you through the exam format, all six sections of the current Body of Knowledge and how many questions each one carries, the official resources worth using, and the questions candidates ask most often.

What Is the ASQ CSSGB Exam?

The CSSGB is ASQ’s credential for professionals who work on Six Sigma improvement projects, usually as part of a team led by a Black Belt, or as the leader of smaller projects in their own area. A Green Belt understands the DMAIC method (Define, Measure, Analyze, Improve, Control), can collect and analyze process data, and knows how to keep improvements from slipping after a project ends.

The exam is not a vocabulary quiz. Many questions give you a short scenario or a data set and ask you to pick the right tool, calculate a statistic, or interpret a result. It’s also open book, which rewards candidates who can find a formula in seconds.

What Is the CSSGB Exam Format?

Here’s the exam at a glance, based on ASQ’s Six Sigma Green Belt certification page and exam FAQs:

  • Questions: 110 multiple-choice questions on the computer-based exam.
  • Scored vs. unscored: 100 scored questions and 10 unscored questions that ASQ is testing for future use. They aren’t labeled, so treat every question as if it counts.
  • Time: 4 hours and 18 minutes of exam time within a 4.5-hour appointment. There are no scheduled breaks, and the clock keeps running if you step away.
  • Delivery: Computer-based through Prometric during ASQ’s testing windows, in English. ASQ also offers a 100-question, four-hour paper-and-pencil version in Mandarin in certain locations.
  • Open book: You may bring your own references, but everything, including notes, must be bound and stay bound. Sticky notes are allowed only as tabs attached before you arrive.
  • Calculator: An on-screen basic scientific calculator is provided. Silent, battery-operated calculators without programmable memory are allowed. Programmable and graphing models, such as the TI-89, are not allowed.
  • Passing score: 550 out of a possible 750 on ASQ’s scaled score.
  • Results: Computer-based candidates see a preliminary result on screen when they finish, followed by official results by email.

With 258 minutes for 110 questions, you have about 2 minutes and 20 seconds per question. Calculation items and time spent searching your references add up quickly.

What Body of Knowledge Does the CSSGB Exam Use?

The current exam is based on the CSSGB Body of Knowledge (BoK) effective in 2022. It replaced the 2014 BoK, which had five sections and combined Improve and Control. The 2022 version follows the full DMAIC cycle, with Improve and Control as separate sections, and lists a cognitive level (such as Remember, Understand, Apply, or Analyze) for each topic. That level tells you how deeply a topic is tested.

Here is how the 100 scored questions are divided:

  • I. Overview: Six Sigma and the Organization: 11 questions
  • II. Define Phase: 20 questions
  • III. Measure Phase: 20 questions
  • IV. Analyze Phase: 18 questions
  • V. Improve Phase: 16 questions
  • VI. Control Phase: 15 questions

I. Overview: Six Sigma and the Organization (11 Questions)

This section sets the big picture: why organizations invest in Six Sigma, how projects connect to business goals, and how Lean and design-focused methods fit alongside DMAIC.

  • The value of Six Sigma, organizational goals, and the drivers and metrics used to select projects.
  • Lean concepts and value stream mapping.
  • Design for Six Sigma (DFSS) roadmaps, such as DMADV.
  • Basic failure mode and effects analysis (FMEA), including design FMEA and process FMEA.

Study tip: Know how the risk priority number (RPN) is calculated (severity x occurrence x detection) and why a high severity rating may need action even when the RPN is modest.

II. Define Phase (20 Questions)

Define is about choosing the right problem and setting the project up to succeed. It covers both project mechanics and the people side of improvement work.

  • Project identification: selection, process elements, benchmarking, inputs and outputs (for example, SIPOC), and owners and stakeholders.
  • Voice of the customer (VOC): identifying customers, collecting customer data, and translating it into requirements, such as critical-to-quality (CTQ) characteristics.
  • Project management basics: the project charter, scope, metrics, planning tools, documentation, risk analysis, and closure.
  • Management and planning tools, including affinity diagrams, tree diagrams, and matrix diagrams.
  • Business results, including process performance measures and communication.
  • Team dynamics: stages of team development, roles and responsibilities, team tools, and communication.

What questions look like: A team keeps adding new problems to its project. The best answer usually involves going back to the charter and scope, not expanding the project or abandoning it.

III. Measure Phase (20 Questions)

Measure establishes a reliable baseline. This is where the statistics start in earnest, so plan for plenty of practice time.

  • Process analysis and documentation, such as process maps and flowcharts.
  • Basic probability concepts and the central limit theorem.
  • Statistical distributions, including normal, binomial, Poisson, t, chi-square, and F.
  • Collecting and summarizing data: data types and measurement scales, sampling and data collection plans, descriptive statistics, and graphical methods.
  • Measurement system analysis (MSA), including gauge repeatability and reproducibility (GR&R).
  • Process and performance capability: Cp, Cpk, Pp, and Ppk, and short-term versus long-term capability.

Study tip: Be fluent with capability formulas. Cp = (USL – LSL) / 6σ measures potential capability, while Cpk = the smaller of (USL – mean) / 3σ and (mean – LSL) / 3σ also accounts for centering.

IV. Analyze Phase (18 Questions)

Analyze is where you find out which inputs actually drive the problem, using data rather than opinions.

  • Exploratory data analysis: multi-vari studies, correlation, and simple linear regression.
  • Hypothesis testing basics: null and alternative hypotheses, significance level, Type I and Type II errors, power, and p-values.
  • Tests for means, variances, and proportions.
  • Additional analysis methods, including gap analysis and root cause analysis.

What questions look like: Expect to choose the right test for a situation, calculate a test statistic, or decide whether to reject the null hypothesis given a p-value.

V. Improve Phase (16 Questions)

Improve covers how you develop, test, and roll out solutions.

  • Design of experiments (DOE): basic terms such as factors, levels, responses, replication, randomization, and interactions, plus main effects and interaction plots.
  • Implementation planning for solutions.
  • Lean tools: waste elimination, cycle-time reduction, and kaizen and kaizen blitz events.

Study tip: Practice reading interaction plots. Non-parallel lines signal an interaction, meaning one factor’s effect depends on the level of another.

VI. Control Phase (15 Questions)

Control focuses on ensuring gains last after the project team moves on.

  • Statistical process control (SPC): basics, rational subgrouping, and selecting and interpreting control charts.
  • Sustaining improvements: control plans, document control, training plans, audits, and the plan-do-check-act (PDCA) cycle.

Study tip: Know which chart fits which data. X-bar and R or X-bar and s charts are for variable data in subgroups; individuals and moving range charts are for single measurements; and p, np, c, and u charts are for attribute data.

How Should You Use the CSSGB Blueprint to Build a Study Plan?

The BoK is your master checklist. Here’s how to turn it into a plan:

  1. Take a baseline. Answer a mixed set of practice questions before you review anything.
  2. Weight your time. Define and Measure together are 40 questions, and adding Analyze brings you to 58. Give the statistics-heavy sections the most hours, but don’t skip the Overview section’s 11 questions.
  3. Map every miss to a BoK topic. Note the section and subtopic of each missed question, and patterns will show up fast.
  4. Build your reference kit early. Since the exam is open book, tab your main reference by BoK section and create a bound formula sheet. Practice with exactly what you’ll bring.
  5. Finish with timed, mixed practice. In the last few weeks, work at exam pace so roughly two minutes per question feels normal, including time to look things up.

What Official Resources Should You Use?

Commonly used CSSGB study textbooks:

  • The Certified Six Sigma Green Belt Handbook, Second Edition (ISBN 978-0873898911)
  • Six Sigma: A Complete Step-by-Step Guide: A Complete Training & Reference Guide for White Belts, Yellow Belts, Green Belts, and Black Belts Paperback (ISBN 978-1732592650)
  • The ASQ Certified Six Sigma Green Belt Handbook, 3rd Edition (ISBN 978-1636940298)

Frequently Asked Questions About the CSSGB Exam

What is the passing score for the CSSGB?
You need 550 out of a possible 750. ASQ sets a raw cut score through a standard-setting process and converts it to that scale, so there’s no fixed percentage of questions you must answer correctly.

How soon will I get my CSSGB exam results?
On the computer-based exam, you see a preliminary result on screen when you finish. Official results follow by email, typically within about a week.

Is the CSSGB really open book?
Yes. You may bring bound references and bound notes. Loose pages, paper-clipped materials, and question-and-answer collections (unless the questions are removed) aren’t allowed, and a test center administrator inspects everything before you enter.

How many times can I retake the CSSGB exam?
ASQ doesn’t limit retakes, but each one carries a retake fee. You can’t retake in the same testing window, and you must retake within two years of your last attempt or submit a new application.

Has the CSSGB Body of Knowledge changed recently?
The current exam follows the 2022 BoK, which separated Improve and Control into their own sections and added topics such as implementation planning and sustaining improvements. If you’re using an older guide built on the 2014 BoK, check its coverage against the current BoK.

Do I need to recertify for the CSSGB?
No. ASQ lists the CSSGB as a lifetime certification with no recertification requirements.

Start Preparing for the ASQ CSSGB Exam With Pocket Prep

A clear blueprint and steady practice are a winning combination. Pocket Prep’s ASQ CSSGB practice questions include 1,000 exam-style questions across all six BoK sections, each with a detailed explanation that walks through the reasoning and math. Use Build Your Own Quiz to focus on Measure or Analyze, then switch to Timed Quiz sessions to build your pace. You’ve got this, one DMAIC phase at a time.