Six Sigma Green Belt Course: What It Covers, What It Costs and How to Choose

Course, exam and certificate: the difference

People use “Green Belt certification” for three different things:

• A course teaches you the material. It may include a project, and the provider issues its own certificate.
• An exam from an independent body, such as ASQ or IASSC, tests what you know. It is separate from any course.
• A belt from your employer usually means you completed company training and delivered projects with results.

ASQ describes the Green Belt as a professional who works alongside or under a Black Belt on quality improvement projects. Its Green Belt exam has 110 questions (100 scored), is open book, and requires three years of full-time paid work experience in the Body of Knowledge, with no education waiver. Fees, requirements and the IASSC alternative are laid out in our Six Sigma certification guide, so this page focuses on choosing a course. For how Green Belts fit with other levels, see Six Sigma belt rankings.

Two real examples

These two university-run programs show how much courses vary. We use them as examples of the range, not as recommendations. Figures are from each program’s own page and may have changed, so check before you enroll.

The key difference is the project. One makes you improve a real process and show results. The other teaches through case studies. Neither page mentions an exam, so neither replaces an independent credential such as ASQ’s.

Cheaper options exist too. Marketplaces such as Coursera and Udemy list Six Sigma courses at a wide range of prices and depths. We may earn a commission if you sign up, at no cost to you. We are not affiliated with any university. Check each syllabus and update date.

What the course should cover

The best checklist is ASQ’s own 2022 Certified Six Sigma Green Belt Body of Knowledge, available as a PDF on asq.org. Its six sections and the number of exam questions for each are below.

A course aimed only at the work (not the exam) may weigh topics differently. Even so, if a syllabus skips measurement system analysis, hypothesis testing or control charts, ask why. For the overall method, read our DMAIC guide, and for the background what Six Sigma is and Six Sigma vs Lean Six Sigma.

The Green Belt project

A project turns knowledge into evidence. It gives you a concrete story to tell: the problem, the data, the fix and the result. OU’s program counts a project as complete once there is evidence of improvement on the goals, through a pilot or full implementation, supported by a written report.

Pick a project that is small enough to finish in a few months, has a measurable problem and sits within your authority. A charter keeps it focused.

The maths, with one worked example

You do not need advanced mathematics, but you do need to be comfortable with averages, spread and basic tests. The most common Measure-phase calculation is process capability. It asks: does the process fit inside the customer’s limits?

• Cp = (upper limit − lower limit) ÷ (6 × standard deviation). It shows the potential if the process were centred.
• Cpk = the smaller of (upper limit − mean) ÷ (3 × standard deviation) and (mean − lower limit) ÷ (3 × standard deviation). It also reflects how well centred the process is.

Our illustration, with made-up numbers: a part must measure between 9.5 and 10.5 mm. The process averages 10.1 mm with a standard deviation of 0.12 mm.

Cp of 1.39 says the process is capable of fitting the limits. Cpk of 1.11 is lower because the average sits closer to the upper limit. Re-centring the process towards 10.0 mm would raise Cpk without reducing variation. Target values for Cpk differ by industry and customer, so use the one in your own specification.

How to judge a course

Different bodies publish different standards, so “accredited” means little unless the provider tells you by whom. Ask what the certificate will let you do, and whether employers you care about accept it.

A 10-week study plan

This plan suits someone preparing for a Green Belt exam alongside a job, spending roughly 5 to 7 hours a week. It follows the Body of Knowledge, which is our own arrangement and not an official schedule.

1. Week 1: Overview. Six Sigma goals, lean principles and Design for Six Sigma.
2. Week 2: Define. Project selection, voice of the customer, charters, team basics.
3. Week 3: Measure, part 1. Process maps, data types, probability.
4. Week 4: Measure, part 2. Distributions, sampling and summarising data.
5. Week 5: Measure, part 3. Measurement system analysis and process capability.
6. Week 6: Analyze, part 1. Exploratory data analysis, charts, correlation.
7. Week 7: Analyze, part 2. Hypothesis tests and confidence intervals.
8. Week 8: Improve. Design of experiments, lean tools, implementation planning.
9. Week 9: Control. Control charts, control plans, sustaining gains.
10. Week 10: Mixed practice questions, then review weak areas.

If your exam is open book, as ASQ’s is, spend part of each week organising your reference notes, since you must bring your own bound materials.

Costs to plan for

Ask your employer about training budgets. Some organizations pay for belts that link to improvement goals.

Steps to get started

1. Decide your goal: a skill, a credential or a promotion.
2. Check the exam rules if you want ASQ’s credential, including the three-year experience rule.
3. Pick a course type using the table above.
4. Find a project at work before you start, so you can apply lessons straight away.
5. Collect real data early. Most projects stall on data.
6. Record results in a one-page summary: problem, method, change, result.

Also see Lean Six Sigma certificates and the Six Sigma hub.

Frequently asked questions

What is a Six Sigma Green Belt course?

A training program that teaches the DMAIC method and basic statistics so you can lead or support process improvement projects.

How much does a Green Belt course cost?

It varies widely. Two university-run examples list $2,195 and $2,495. Online marketplace courses are often cheaper. The independent exam is a separate cost.

How long does a Green Belt course take?

Purdue’s course lists 10 weeks and about 45 hours. OU’s lists 16 to 26 weeks including a real project.

Is a course the same as certification?

No. A course gives you a provider certificate. Independent certification, such as ASQ’s, requires passing an exam, and ASQ also requires three years of work experience for the Green Belt.

Do I need statistics before I start?

Neither example lists a prerequisite. Basic comfort with averages and graphs helps, and good courses teach the rest.

Is Green Belt worth it?

It depends on your goal. It is most useful if you can apply it to real projects. A certificate alone does not guarantee a job or a raise.