A Guide to Carbon Steel Grades (Plus a Chart)

From the lugnuts holding your vehicle’s tires on to beams supporting up the bridges you drive over, there’s a good chance you’ll find carbon steel.

When considering which type of steel is best for your project, carbon steel can be a bit tricky to understand. After all, all steel does contain carbon. And there are many carbon steel grades with unique qualities to choose from.

To make things easier for your evaluation, we’ve compiled a carbon steel grades chart highlighting the most commonly used carbon steel grades and their applications.

Use the information below to get the right carbon steel grade for your project.

A Guide to Carbon Steel Grade Levels

Before diving into our carbon steel grade chart, let’s first explore the different levels of this material. Selecting the right carbon steel level has big implications on your finished pieces. With the wrong level, your final product can fail when used.

An alloy comprising iron and carbon, most folks divide this steel type into four levels based on its carbon content:

Low carbon steel (mild steel): Typically consists of 0.04% to 0.3% carbon. Depending on the properties you need, you can opt for a type with a certain element added or increased. (Ex.: In structural steel, carbon and manganese content is higher.) Low-carbon steel is found in cookware, pipelines, and fencing.

Medium carbon steel: Generally contains between 0.31% and 0.6% carbon, plus 0.06% to 1.65% manganese. Stronger than low-carbon steel, but harder to weld, form, or cut. Often hardened and tempered via heat treatment. This level of carbon steel is used for axle shafts, train wheels, and structural support beams.

High carbon steel: Commonly known as “carbon tool steel.” Typically has a carbon range between 0.61% and 1.5%. Very difficult to bend, weld, or cut. Once heat-treated, it becomes quite hard and brittle. Applications include cutting tools and masonry nails.

Ultra or very high-carbon steel: Though an extremely strong metal, this material is brittle and requires special handling. It contains between 0.96% and 2.1% carbon. Through processing with alloys, ultra high-carbon steel becomes one of the most durable carbon steels on the market. It’s often used for truck springs, metal cutting tools, or knives.  

To enhance strength and reduce brittleness, carbon steel pieces may include traces of other elements, such as:

Manganese, up to a 1.65% maximum

Silicon, up to a 0.6% maximum

Copper, up to 0.6% maximum

Carbon Steel Grades Chart: The Most Popular Grades and Uses

Here are the most common carbon steel grades, in chart form. As some of the most popular carbon steel grades, crusherparts they’re tried, trusted, and true in each of their respective applications.