The Best Combination Squares

The Best Combination Squares

There is a wide variety of measuring tools available; a combination square is perhaps one of the most versatile. Combination squares not only measure depth and length but also check 45-degree and square angles. Furthermore, most combination squares also include a simple bubble level. The right combination square can replace several of the tools that you have in your shop. It’s a valuable piece in the tool kit of DIYers and contractors.

Numerous combination square models are available, so I understand that it can make choosing the single best combination square challenging. The following guide delves into their specifications and should make selecting the right one for you a little bit easier.

What is a Combination Square?

A combination square is a multi-use measuring tool that is primarily used for ensuring that a 90° angle is accurate, measuring a 45° angle, measuring the center of a circular object, finding depth, and simple distance measurements. The versatility of the combination square ensures its dominance over any other square in its class.

The Best Combination Squares – Buying Guide


Combination squares are made from a wide variety of materials in various specifications and different sizes. Some combination squares are designed as general-purpose tools, while others are for more detailed tasks. 

Size and Accuracy

In combination squares, size generally relates to the length of the ruler section. The ruler section, also known as the blade, can run from 4 inches on the smallest models to 24 inches on the largest.

While a 4-inch combination square is compact and easy to stow in a toolbox, a longer blade is better when checking lay out. A 12-inch combination square, probably the most practical size for general use, is the most popular option. 

The accuracy of the square is going to depend on both the tool’s manufacturing technique and material. The blades are marked in different ways. On low-cost combination squares, the blade is punched out of sheet metal, with the markings created by the same punch, which often leads to markings that are slightly fuzzy. Other markings are painted, which can wear over time, making the scale difficult to read. On better combination squares, the markings are machine etched, resulting in sharper lines, which helps provide greater precision.


Blades, or the ruler sections, are usually made from stainless or hardened steel. Hardened steel is very strong, but I was to stress that it must be cared for properly to avoid rust. To help prevent rust, some combination squares are also chrome plated. Stainless steel is very durable but has slightly less strength than hardened steel. However, it does resist corrosion. The blade thickness can also vary considerably. 

The head on combination squares can be made of plastic, also known as frequently high-impact polystyrene, die-cast zinc, or cast iron. Plastic heads don’t cost much to produce, reducing the price of the combination square overall. However, heat might cause distortion. 


You can use a combination square for a wide range of measuring and marking tasks, both in the workshop or on the job site. The blade can be removed and used as a ruler. The bubble level can be used to check alignment when installing things like doorframes. You can also make combination squares more versatile by using interchangeable heads. These are often included in four-piece combination square sets. 


There are several applications that combination squares can be used for. I would like to mention again that the best quality combination squares feature cast-iron heads with precision-etched blades and finely ground-bearing surfaces. However, these are not necessary for you since they’re intended for engineering shops. They’re very expensive tools.

On the other hand, many combination squares are ideal for a wide range of DIY uses. Should they get damaged, replacements are pretty affordable. In between those extremes, lots of combination squares of different sizes are designed for furniture makers, remodelers, hobbyists, welders, and more.

The Best Combination Squares

Here are some of the best combination squares you can purchase today. 

Starrett-11H-12-4R Combination Square

The Best Combination Squares

The Starrett-11H-12-4R Combination Square is constructed and machined with high standards to ensure you’re getting a quality item. The blade of the combination square is made with hardened, tempered steel. This means it’s very durable; you don’t have to worry about it being fragile. The markings on the square are machine etched into the surface, so they won’t wear off. This is a common problem for combination squares that have markings that are punched or painted. The square also has a reversible lock bolt that allows the user to switch over the blade without removing the nut.

The head on the Starrett-11H-12-4R Combination Square is made from cast iron and finished with a black, corrosion-resistant finish. The finely ground-bearing surfaces help ensure that angles are accurate. A scriber and bubble level are included. The Starrett is definitely an investment, but you get a great precision tool that’s perfect for engineers. It may be a little pricey for DIYers and contractors.

Irwin Tools 12” Combination Square


The Irwin Tools 12” Combination Square is another excellent choice. I’ve been using Irwin tools for years and have always been impressed with the quality that I get, especially when combined with the reasonable prices. The blade on this combination square is rustproof stainless steel. The body is made from cast zinc. The combination of these materials makes the product nice and durable. You don’t have to worry about wearing out this product, even if you’ll be using it frequently. 

The 12-inch length of this square is also long enough to be useful for larger marking and measuring tasks. The markings are black etched, making them easy to read. You’ll also be happy to know that said markings won’t fade or rub off over time. It features both metric and standard measurements, one on either side of the blade, making it more versatile when using it as a simple measuring tool!

Mr. Pen- Combination Square

The Best Combination Squares

Are you looking for a combination square that’s cheap and will get the job done correctly? If so, I have the perfect combination square for you. The Mr. Pen- Combination Square is dirt-cheap and fully functional. Both of those things are the reason why I added it to the best combination squares list; I think it’s one of the best combination squares for the money.

This combination square is 12 inches long and has markings that go down to 1/32 inches. The blade is made from stainless steel, which makes it completely rust-proof and easy to read. There’s even a built-in bubble level, and a brass scriber helping expand this tool’s versatility.

However, I would like to mention if you’re looking for a combination square that you can use on a daily basis, you may want to reconsider getting this square. This combination square is best for hobbyists and non-professionals who want accurate measurements and markings on their projects. 

WORKPRO Rafter Square and Combination Square Tool Set


The WORKPRO Rafter Square and Combination Square Tool Set have a blade made from stainless steel that offers etched markings starting at 1/32-inch and 1-millimeter divisions. The head of the square is sturdy and made from die-cast zinc. There’s also a bubble level, and scriber included.

This combination square is very versatile; the tool contains a host of common spacings and angles precut into it, with slots designed for a carpenter’s pencil to fit into each. The WORKPRO rafter square is 13/64-inch-thick aluminum. The 7/8-inch fence also can be used as a circular saw guide when crosscutting lumber.

Empire E280IM Heavy Duty Combination Square

The Best Combination Squares

Empire tools are always a great choice to go with, and the Empire E280IM Heavy Duty Combination Square is a fine option for both amateurs and professionals. The true-blue bubble vial is easy to see, and the draw bolt on the combination square is simple to tighten and loosen when adjusting the head. The Empire E280IM Heavy Duty Combination Square features both standard and metric markings. It weighs 12.8 ounces, making it lighter than what you might think for such a large combination square. 

I would like to mention that since this combination square is 16-inches in length, it’s great for longer measurements. But you may find it inconvenient to use it for smaller tasks that require a less bulky option.

Frequently Asked Questions

This guide provides information on the key features of the best combination squares. However, given the variety of tools available and their various uses, you may find that a number of questions may remain. The following questions have answers that address those frequently asked questions.

Q: How do I use a combination square?

Combination squares are pretty easy to use, and their versatility is one of their main attractions. Combinations squares include a ruler, which you can use to check the length and use the handle as a base for checking height or depth recesses. Use the “square” portion of the combination square to check or mark 45 and 90-degree angles. If your combination square includes a bubble, it can be used to check and make sure things are level.

Q: How do I maintain a combination square?

It’s important to maintain all of your tools, including a combination square. With most tools, you’ll find that dirt is the main problem. Periodically disassemble and clean the components of the combination square with a nonabrasive scourer and a little rubbing alcohol to remove any deposits. After the components dry, give the blade of the combination square a light wipe with paste wax to lubricate it.

Q: How accurate are combination squares?

The accuracy of the combination square depends on the model and the combination squares age. Many squares are manufactured to tolerances of 0.001 inches; however, friction can eventually impact the guideways and screw threads, loosening them over time. 

Q: How do I know if a combination square is accurate?

The good news is, it’s relatively easy to test a combination square’s accuracy. All you need to do is get a piece of board with a flat edge and place the combination squares head at one end of the ruler and place the tool against the edge of the board as if checking for a square. With a sharp pencil, draw a line along the blade of the square. Flip the combination square over so the head creates a mirror image. Place the base of the combination square at the bottom of the first line and draw a second line along the blade. The two lines should be parallel. If they form a shallow “V,” the square is not accurate and should be calibrated.

Wrapping Up

There are the best combination squares! We hope this buying guide helped you find a combination square that’s best for you! Do you have a favorite combination square from this list? Do you own a combination square already? If not, are you considering purchasing one now? Please feel free to leave a comment, I would love to hear from you! 

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About Brianna Goulet

Brianna is a freelance writer who covers home decor, DIY projects, and tool reviews. She’s written for a variety of sites on these topics. She's originally from Massachusetts but she's currently living in Florida.

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