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If you’ve spent some time around mechanical engineering or manufacturing, then you might have heard of GD&T. But what is it? And why is it relevant to your product design project?

Geometric Dimensioning and Tolerancing (or GD&T) is a system for defining and communicating the tolerances of size, shape, orientation, and location for features on mechanical parts. It uses a set of symbols to convey this information clearly and concisely. GD&T is important because it helps ensure that manufactured parts meet the designer’s intent and are interchangeable with other parts. In other words, GD&T ensures that products are made to specifications.

A language for designers and manufacturers

There are three main benefits of using GD&T in product design:

– improved communication between designers and manufacturers

– increased accuracy of manufactured parts

– reduced cost of rework due to errors.

Using GD&T can help you avoid costly mistakes in manufacturing, improve communication between designers and engineers.


GD&T is effectively a language for designers and manufacturers to communicate about what is an acceptable part.

One common problem that can be avoided with GD&T is mismatches between parts. For example, if two parts are supposed to fit together but don’t, GD&T can help identify the mismatch and prevent the part from being manufactured. GD&T can also help reduce the cost of rework due to errors. By specifying the tolerances of size, shape, and location for features on a part, GD&T can help ensure that the part is manufactured accurately the first time. This can save time and money in the manufacturing process.

Part of our design toolkit…

At Emergnt Design Labs, we use GD&T to ensure our clients’ success. We work closely with our clients to understand their needs and specifications, and then use GD&T to create detailed drawings that accurately communicate those requirements to our manufacturing partners. This ensures that our clients’ products are made to the highest standards and meet their exact specifications.

GD&T is an essential part of our design toolkit, and we know that- depending on the project needs, it’s crucial to ensuring the accuracy and interchangeability of manufactured parts. We are confident in our ability to use GD&T effectively, and we are committed to providing our clients with the best possible product design services.

Jeremy Nashed

A product design expert, Jeremy cultivated his skills working in manufacturing and rapid prototyping facilities. His design experience ranges from consumer products to government contracting, and he is known for end-to-end support on every project.

M.S. in Mechanical Engineering, Georgia Institute of Technology.