3 years of full-time paid work in the Green Belt Body of Knowledge
RequiredThe work can be in one or more of the six Body of Knowledge areas. Internships, co-ops and coursework do not count, and ASQ grants no education waivers.
Certified Six Sigma Green Belt (CSSGB) Exam Guide
Validates knowledge of the DMAIC method, lean tools and the statistics needed to lead Six Sigma process-improvement projects.
The exam checks that you can run a DMAIC project: choose and scope it, measure and analyze with statistics, then improve and control the process. It is open book, so learn the concepts first, then build a tabbed reference that lets you find a formula or tool definition in under a minute.
Understand the exam
Syllabus
IOverview: Six Sigma and the organization11 questions
- ASix Sigma and organizational goals
- BLean principles in the organization
Example scenario: A value stream map shows 40 minutes of waiting between two steps that each take 3 minutes. Which lean waste is this, and which tool would you use to shorten it?
IIDefine phase20 questions
- AProject identification
- BVoice of the customer (VoC)
- CProject management basics
- DManagement and planning tools
- EBusiness results for projects
- FTeam dynamics and performance
Example scenario: A clinic has eight complaint categories and wants to “improve satisfaction.” Which voice-of-the-customer tool turns them into measurable requirements, and what would the charter’s problem statement say?
IIIMeasure phase20 questions
- AProcess analysis and documentation
- BProbability and statistics
- CStatistical distributions
- DCollecting and summarizing data
- EMeasurement system analysis (MSA)
Example scenario: A process has a mean of 10.02, a standard deviation of 0.05 and specification limits of 9.90 and 10.10. Which index shows whether it is both capable and centred, and how do you calculate it?
IVAnalyze phase18 questions
- AExploratory data analysis
- BHypothesis testing
- CAdditional analysis methods
Example scenario: You have 30 fill weights from each of two machines. Which test compares their means, and what does a p-value of 0.03 mean for your decision?
VImprove phase16 questions
- ADesign of experiments (DoE)
- BImplementation planning
- CLean tools
Example scenario: A press changeover takes 90 minutes, and half of it happens while the machine is stopped. Which lean technique targets this, and how would you pilot the change?
VIControl phase15 questions
- AStatistical process control (SPC)
- BSustain improvements
- CLean tools for process control
Example scenario: You track defects per invoice, and the number of invoices varies each day. Which control chart fits, and what pattern would signal a special cause?
Official CSSGB Body of Knowledge · 2022 BoK
Format
- Questions
- 110
- Duration
- 4h 18m
- Passing score
- 550 / 750
- Delivery
- Test centre or online
- Languages
- English
Question types
Multiple choice. Choose the single best answer from four options.
CertUp example
A process has a mean of 50, a standard deviation of 2, and specification limits of 44 and 56. What is its Cp?
Show answer
B. 1.0. Cp = (USL − LSL) / (6σ) = 12 / 12 = 1.0.
Eligibility and booking
Apply on asq.org for a testing window and pay the fee; online applications are reviewed in one to two business days. After approval, ASQ emails a Prometric eligibility ID so you can book a test centre or remote appointment. CSSGB runs in even-numbered months, and your eligibility covers three consecutive windows from the one you choose. The next window is December 2026; apply by November 9, 2026.
Make a study plan
Read the Body of Knowledge and try a short practice set first, so you can see which sections are weakest. Spend most of your time on the sections where you score lowest, which is often the statistics.
Most candidates spend 50–100 hours. Plan for the low end if you use Six Sigma tools and statistics regularly; add time if hypothesis testing or capability indices are new.
- 1Understand the examRead the syllabus and format, check you’re eligible and pick a target date.4 h
- 3Learn the core conceptsWork through one main course or book, topic by topic.48 h
- 4Practice with mock examsTake timed practice tests and review every mistake.24 h
- 5Prepare for exam dayBook the exam and check the ID and delivery rules.4 h
Learn the core concepts
The ASQ handbook is written to the Body of Knowledge and doubles as your open-book reference. Add a video course if you prefer guided lessons.
Best official courseCSSGB Certification Preparation
Best video courseCertified Lean Six Sigma Green Belt Training (Accredited)Best short courseCertified Lean Six Sigma Green Belt (2026)Build your own index. One passer built a glossary of terms and equations with handbook page numbers and had it bound. Sticky tabs must be attached before you arrive.
Practice with mock exams
Practice shows where you lose points. Rework hypothesis-test choice, capability indices and control charts until you can explain the answer, then time at least two full sets.
Official question bankASQ CSSGB Question Bank
CSSGB Free Practice TestsASQ Certified Six Sigma Green Belt Study Guide, 2nd EditionAre you ready?
- You can choose the right hypothesis test and control chart for a scenario.
- You can calculate DPMO, RTY, Cp and Cpk without looking up the formula.
- You can find any Body of Knowledge topic in your reference within a minute.
- You finish a timed 100-question set with time to review.
Prepare for exam day
Bring accepted ID and bound references, and follow the checklist for your delivery route.
Before travelling to Prometric
Before testing with ProProctor
- Arrive 30 minutes early. Late arrivals cannot test and lose the fee.
- Bring valid government-issued photo ID; the name must match your scheduling notification exactly.
- Bring bound references only; staff inspect them before you enter.
- Bring a silent, non-programmable calculator or use the on-screen one.
- Belongings go in a locker; scratch paper and pencils are provided.
- Run the Prometric system readiness check when you book and again shortly before the exam.
- Use a stable, preferably wired connection. Connection failures on your side mean a $130 reschedule fee.
- Have valid government-issued photo ID and your bound references ready.
- Scratch paper and pens are not allowed; use the on-screen scratchpad.
- You may take up to three 10-minute breaks; tell the proctor before leaving the camera view.
- Change an appointment at least five days ahead on Prometric’s site; the fee is $130.
- There are no scheduled breaks at a test centre, and the clock keeps running if you leave the room.
Remote proctoring is not available in China, Saudi Arabia, the United Arab Emirates, Qatar or Pakistan.
Advice from exam takers
Tab the handbook and learn where things are.
One passer printed the third edition handbook, wrote page numbers beside keywords and practised finding where each practice answer sat. Another built a 60-page glossary of terms and equations with page references and had it bound.
Use the third edition.
Two commenters say a lot changed from the second edition and recommend the third edition handbook with the ASQ study guide.
Expect statistics and control charts.
A passer who tested remotely in June 2026 describes about 70% concept questions and 30% calculations such as RTY, probability and hypothesis testing, with many questions on SPC and picking the right test. Another passer says the math is simple but hypothesis testing needs to be solid, and flags questions to return to.
Plan to use the full time.
Two passers report using nearly the whole sitting, in one case in three passes, with the last pass spent catching misread options.