Difference Between Lean and Six Sigma

Lean vs Six Sigma

For successful running and continuous development of a business, both lean and six-sigma play a vital role. Though six-sigma is based upon philosophy and lean is based upon techniques, both business strategies run side by side to take a business up to sky limits. Lean is one of those key techniques, which are a part of six-sigma methodology.


Lean is improving flow process of any product during its production. In simple words, lean focuses on reducing wastes during any process and ultimately raise the speed of process. There are two concepts of lean. One concept is called “Just-in-time” and the other one is “Jidoka”. “Just-in-time” means organizing a production process in such a manner that chances of accumulating stock will be reduced up to minimum level. On the other hand, Jidoka means indicating and preventing any wrong points in production line, which could become a cause of producing bad product. The flow chart of lean is such that: identifying value, defining value stream, determining flow of process, defining pull and finally improving process. Because, lean deals with over production, therefore it is inventory based.


Six-sigma means reducing process variation of any product during its production. In short, six-sigma is a management philosophy of reducing quality problems in a running process. Its data oriented methodology is based upon research and deals with parts of process. By using this technique, we can overcome the variation of process by approaching the root cause of problem. The flow chart of six-sigma is defining the problem, measuring the problem, analyzing the process, improving the problem and control over problem. With the help of six-sigma, an infrastructure of expert people, in quality management methods, can be developed. For implementation of six-sigma, process data is required, so that based on this data some positive changes could be brought about to improve the process. There are three concepts in six-sigma. The first one is DMAIC, the second one is DMADV and the third one is Lean.

Lean vs. Six Sigma

• Lean focuses on removing wastes and idleness, while six-sigma eradicate variation in process.

• Lean is a technique of improving process. On the other hand, six-sigma is a philosophy of running process in streamline.

• The aim of lean is to raise production by increasing efficiency of process. On the contrary, six-sigma defines and satisfies client’s requirements.

• Lean deals with running setup of process, while six-sigma deals with quality of product.

• Lean tools are visual oriented like Microsoft Visio; however, six-sigma tools are mathematics and statistics.

• Lean is a continuous process and is daily based, while six-sigma is not because of its philosophical methodology of reducing process variation


No doubt, lean is based upon waste and production methodology and the aim of six-sigma is perfection of product. However, it is fact that it is impossible to develop a process and finally business without giving equal attention towards both techniques, as the ultimate goal of both methodologies is same that is profitable business.