GMAW MIG Welder: What the Name Really Means

All Posts learn Weld Gear Team Last updated on October 13, 2026

Shopping for a welder, you may see the same machine described as a MIG welder in one place and a GMAW welder in another, and reasonably wonder whether they are different things you need to choose between. They are not. GMAW and MIG are two names for the exact same welding process, and a GMAW MIG welder is simply a MIG machine described by its technical name. Understanding this clears up a surprising amount of confusion and helps you shop with confidence.

This guide explains what GMAW means, why it is identical to MIG, and how the machine works so you know precisely what you are buying.

GMAW and MIG are the same thing

Let us settle the core point first, because it is the whole reason for the confusion.

GMAW stands for Gas Metal Arc Welding, which is the formal, technical name used in industry, standards, and training. MIG stands for Metal Inert Gas welding, which is the older, more common everyday name for the identical process. They describe the same thing: a welder that feeds a continuous wire electrode through a gun while shielding gas protects the weld. So a GMAW MIG welder is not a special or different machine; it is just a MIG welder labeled with its official name. When you see both terms, treat them as interchangeable.

Why there are two names

A little background makes the dual naming make sense and easy to remember.

The name MIG, Metal Inert Gas, comes from the early days of the process when it used inert shielding gases like argon. As the process evolved to also use active gases like carbon dioxide and blends such as C25, the strictly accurate term became GMAW, Gas Metal Arc Welding, which covers both inert and active gases. So GMAW is the technically precise, modern term, while MIG stuck around as the popular name everyone still uses. You will hear MIG in the shop and on product boxes, and GMAW in textbooks, welding codes, and certification. Both point to the same machine and process.

How a GMAW MIG welder works

With the naming settled, here is what the machine actually does, since that is what matters when you buy one.

A GMAW MIG welder feeds a continuous solid wire from a spool, through the gun, at a speed you set. When you pull the trigger, the wire feeds and an electric arc between the wire and the workpiece melts both, joining the metal, while shielding gas flows from the nozzle to protect the molten weld from the air. You control voltage and wire-feed speed, and many machines set these automatically with an auto-set or synergic feature. A dual-voltage GMAW machine such as the Lincoln Power MIG 211i does exactly this, and would be called a MIG welder on the shelf and a GMAW machine in a welding course.

A note on flux-core

One related term is worth clarifying, since it often appears alongside GMAW and MIG.

Many MIG machines can also run self-shielding flux-core wire, which needs no shielding gas because the wire makes its own shield. The technical name for that process is FCAW, Flux-Cored Arc Welding, which is technically distinct from GMAW even though the same machine often does both. So if a machine is described as GMAW and FCAW capable, it means it can do both gas-shielded MIG welding and gasless flux-core welding. For practical purposes, most affordable wire-feed machines handle both, and the distinction only matters when you care about the precise process name.

What to take away

A GMAW MIG welder is simply a MIG welder called by its technical name, since GMAW and MIG are two names for the identical process.

Three things to remember. GMAW, Gas Metal Arc Welding, and MIG, Metal Inert Gas, are the same thing, so a GMAW MIG welder is an ordinary MIG machine and not a different type to choose. The two names exist because MIG is the popular everyday term while GMAW is the technically precise modern one used in codes and training. And the machine feeds a continuous wire through a gun with shielding gas protecting the weld, often also running gasless flux-core, which is technically the separate FCAW process.

Frequently asked questions

Is a GMAW welder the same as a MIG welder? Yes. GMAW, Gas Metal Arc Welding, and MIG, Metal Inert Gas, are two names for the identical process and machine. A GMAW MIG welder is just a MIG welder called by its technical name.

What does GMAW stand for? Gas Metal Arc Welding. It is the formal, technically precise name used in industry standards, welding codes, and training for the process commonly called MIG welding.

Why are there two names for the same welder? MIG (Metal Inert Gas) is the older, popular name from when the process used inert gases. GMAW became the precise term as active gases like CO2 came into use. Both mean the same process.

Is GMAW better than MIG? Neither is better because they are the same thing. Any difference you see between machines labeled GMAW and MIG comes from the machines themselves, not the naming.

What is the difference between GMAW and FCAW? GMAW is gas-shielded MIG welding with solid wire. FCAW is flux-cored arc welding using self-shielding wire that needs no gas. Many machines can do both processes.

Do I need a special GMAW machine? No. Any MIG welder is a GMAW machine. Buy a MIG welder that fits your metal thickness, power, and gas needs, and you have a GMAW welder by definition.

Will a welding course call it GMAW or MIG? Usually GMAW, since that is the technically correct term used in codes and certification. On product boxes and in the shop, you will more often see MIG. They refer to the same process.