Key difference: The primary difference between the two is the fact that stainless steel is a chromium based steel alloy, whereas mild steel is a carbon based steel alloy. Mild Steel is also known as carbon steel due to the fact that it contains between 0.05–0.25% carbon. Stainless Steel, on the other hand, contains a minimum of 10.5% chromium content by mass.

Stainless Steel and Mild Steel are both widely used products. Both are different alloys of steel, which in itself is an alloy of iron and other elements, primarily carbon. Steel is one of the most common materials in the world, in all of its variations. The steel industry produces more than 1.3 billion tons of steel a year, which is used in a multitude of implications, not limited to buildings, infrastructure, tools, ships, automobiles, machines, appliances, weapons, as well as household items.

Mild Steel is also known as carbon steel due to the fact that it contains between 0.05–0.25% carbon. Stainless Steel, on the other hand, contains a minimum of 10.5% chromium content by mass. Hence, as noted, the primary difference between the two is the fact that stainless steel is a chromium based steel alloy, whereas mild steel is a carbon based steel alloy.

Stainless Steel is known for its high corrosion resistance, which means that it does not stain, rust, or tarnish; a feature that mild steel does not have. Stainless Steel is also very resilient to impact, due to its high level of hardness. Mild steel, on the other hand, does not have the same level of hardness. Instead, it is far more malleable and easy to fabricate due to its carbon content. However, its surface hardness can be increased through carburizing.