What Is Six Sigma? (Including Levels of Certification)

Updated 21 March 2023

Six Sigma is a set of statistical tools, principles and methodologies that has a focus on quality control and improving business processes. There are certifications available to teach people how to master this data-driven procedure. Understanding the Six Sigma process can be useful to amplify your skills and performance in the workplace. In this article, we discuss what Six Sigma is, its methodologies, the levels of certification and the benefits of becoming Six Sigma certified.

What is Six Sigma?

The first step to understanding the answer to, ‘What is Six Sigma?’ is understanding that it's a business process that was developed by a scientist in the 1980s. Scientist Bill Smith intended to create a standardised approach to focus on concerns related to the effectiveness of processes in all areas of an organisation. Since the concept's introduction, many businesses around the world use it to scale their operations and improve their overall performance. This popular data-centric quality control process is based on several core foundations, including:

  • continuous effort is required to achieve the results that help a business thrive

  • operational processes have components that require defining, measuring, analysing, improving and controlling

  • businesses benefit from a unified approach from their entire workforce to achieve sustainable quality and ongoing improvement

  • statistical analysis is critical to success

  • continually evaluating business processes is crucial to sustainable enhancement

  • less variety can mean less error and more income.

Six Sigma methods

There are methodologies for executing Six Sigma effectively, each of which represents the core foundations of the concept. The two prominent methods that managers and engineers use globally are DMAIC and DMADV, which you can find discussed in more detail below.


The aim of this method is to enhance the business's current processes gradually. The acronym represents the following roadmap:

  • Define: clearly defining customers, projects, processes, and business goals

  • Measure: measuring the major elements of current processes for collecting data

  • Analyse: critically analysing collected data to identify any weak spots for improvement

  • Improve: implementing any improvements and verifying their effectiveness

  • Control: continuously overseeing processes to minimise the risk of future inefficiencies.


The aim of this method is to optimise the business's new processes, products or services gradually. The acronym represents the following roadmap:

  • Define: clearly defining customers, projects, processes, and business goals

  • Measure: measuring product efficiency, the competencies of production processes and assessing production risks to collect valuable data

  • Analyse: critically analysing the collected data to identify any weak spots for improvement

  • Design: designing new production processes based on the analysis

  • Verify: conducting testing runs to ensure new production processes produce the desired results.

Six Sigma certification

Individuals may choose to obtain Six Sigma certification to enhance the quality of their output and verify their skills. Many training facilities offer Six Sigma certification, although no one official body of training knowledge or certification exists. Different schools and individual businesses may offer their own variations. Some training institutions and consultancies collaborate to provide an interpretation that they accept. Training can be in a classroom, on-site or online. There's usually also the option to study at your own pace. Students usually receive their certificates upon completing a written exam.

Like karate or martial arts, these certifications have a belt system. Each belt represents a level of skill. Below, you can find more information on the various certification levels you can get to upgrade your workplace performance:

White belt

This is the introductory certification that you can receive, which covers the basics of the Six Sigma process. It can be most suitable for those with no prior formal training. A white belt normally only requires a few hours to complete and doesn't require an exam. An individual with a white-belt certification can assist senior team members with some quality control and sustainability projects.

Related: What Is Quality Assurance?

Yellow belt

The next level is the yellow belt certification, which can provide you with a good foundation knowledge of the Six Sigma principles. A yellow belt certification can take one to three weeks to complete. Employees who hold yellow belts can contribute to projects and assist more senior-level managers. With this certification, you can confidently explain to your colleagues how implementing Six Sigma concepts can benefit them in managing their workload and meeting their goals.

Related: How to Overcome Challenges at Work (A Guide and Examples)

Green belt

Obtaining a green belt can show that you have advanced knowledge of Six Sigma concepts. Completing this level of certification can take from two to seven weeks. With a green belt, it's likely that you can implement Six Sigma principles as part of your everyday tasks. There is also a chance for those who hold a green belt to become project leaders.

Related: What Is a Project Leader? (Duties, Skills and Salary)

Black belt

This advanced level of certification can be most suitable for those with prior foundational Six Sigma knowledge and experience. A black belt can take one to three months to complete. Once you earn this level of expertise, you can have the skill required to lead businesses in changing their business operations for the better. You can achieve proficiency in navigating business challenges and tailoring training methods to the skill level of each employee.

Related: What is Business Development?

Master black belt

A master black belt is the highest level of Six Sigma certification that you can achieve. You can expect to complete a master black belt certification in around two months. Earning this achievement can highlight you as an expert and authoritative team member for producing and developing strategies and determining key performance indicators (KPIs) required for success. Consulting firms often look for candidates with this type of certification. With a master black belt, you can also mentor black and green belts that require additional training and advice.

Related: Understanding Consulting as a Career: Types and Benefits

How to obtain Six Sigma certification

There is no fixed pathway to becoming Six Sigma certified. Below, you can find a few general steps you may consider:

1. Assess your current position

Before you choose which certification to do, it can be a good idea to assess where you are in your career. Doing this can help you choose the certification that aligns most with your career path. For example, if you're a project coordinator, then you're still in the early stages of your career and can consider a lower level of certification. If you're a project manager with significant pre-existing experience working for a business in a particular industry, it could be more beneficial for you to consider a higher-level certification.

2. Review your career goals

Once you evaluate your current position, it can also be helpful to review your goals for the future before choosing a certification. For example, you can consider if you're seeking to make a career in the business and industry in which you currently work. If so, it can help you know that your career goals match your desire to advance within a company. If you're thinking of seeking a different position or changing industries, you could take time to identify the right career path for you before choosing a certification level to ensure it's the right fit.

Related: What's a Six Sigma Resume? (With a Template and Example)

3. Select a certification

Once you have determined your current experience and future career goals, you can identify the right certification. You might choose a white, yellow or green belt if you're just starting your career and want more exposure to solving workplace problems. If you're planning on advancing your current career or seeking a promotion into a more senior role, a black belt or a master black belt may be helpful to you.

4. Enrol in a training program

You can do Six Sigma certifications online or on-site. Either way, you may need to conduct a search to find a suitable training program to enrol in. If you want to enrol at a local training facility, you can localise your search for certifications. If you're happy to study online, you may have many more options for programs to enrol in. It can be a great idea to ask for feedback on professional networking websites to see what experiences other working professionals have had in becoming certified. It may increase your knowledge about various training providers and help you with the enrolment process.

5. Complete the training

Once you complete the enrolment process, it's time to complete your studies. The certification and training provider you choose may affect the time it takes for you to complete this step. Most Six Sigma certifications, except for some white belts, require you to sit an exam upon completion of your coursework. Upon passing your exam, you can receive your certificate.

Benefits of Six Sigma certification

There are multiple benefits of becoming certified in this field, some of which include:

  • Sustainable improvement. When you reach the highest level of Six Sigma certification, you can have confidence in identifying problems and taking corrective measures to enhance a business's performance sustainably.

  • Increased job prospects. Certification can highlight to employers that your performance can be transferable to multiple industries, including human resources, information technology and marketing.

  • Enhanced earning potential. The completion of certifications can showcase your earnings potential, and may also motivate employers to pay you a higher salary because of your experience.

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