As the name suggests, a combination square is the hybrid model of a square tool that combines several tools in one. It has a sliding head similar to the double square. This head also incorporates with built-in miter square and spirit level. Some higher-priced models of combination square come with a protractor and/or center finder. These two tools are also attachable on the blade/rule.
Therefore, it’s a multipurpose tool that allows you to do several jobs in a single tool. Woodworkers, carpenters, metalworkers, and stone masonry take advantage of this tool to check the squareness of corners, check 45-degree angle, measure length, measure angle (by using the protractor), assure levelness (using the spirit level), and find the center point of a round object (using the center finder).
Some of the things that make this tool unique are:
First, it is adjustable. This means that you could use it to transfer measurements that are the same length over and over again. Secondly, if you buy a full set, you will get a protractor head that can measure angles and a center finder head that can help you find the center of objects. Also, the square head comes with a 90-degree and a 45-degree edge, which can be used to check the squareness of corners and make quick scribes at 45 degrees.
Last but not least, the tool can be completely dismantled so that the blade can be used as a stand-alone ruler. And if the blade is highly straight, it can be your straight edge.
If you work on metal or wood, you should have a combination square in your toolbox because it is very useful and would make your work a lot easier.
Top 10 Best Combination Squares in 2023
1. Starrett C11H-6-4R Combination Square [Best Overall]
When it comes to quality combination squares, it is easy to find Starrett products at the top of the list. For the first ranking, Starrett C11H-6-4R combination square is our top pick.
The tool is well-designed with the needs of the customer in mind. It comes with a 6″ blade that would fit most needs. That said, you can fit it into your apron or pocket as well. The satin chrome is used to finish its hardened steel blade which is good for easy reading. Besides, the head is made of cast iron and has a black wrinkle finish.
For the markings, this Starrett C11H-6-4R is photo-engraved and is easy to read because it has black-on-white markings. Some of the things that it has are 4R graduations, a lock bolt, a scriber, and even a spirit level.
This is our top pick for 6 inches size because it is accurate, easy to move about, and fits most of your projects.
- 6″ blade should suit most tasks
- It’s made in the USA
- Satin chrome blade finish doesn’t reflect light, makes you easy to read any markings or graduations on the blade surface
- The graduation type covers 4R
- Head finish is black wrinkle
- Hardened steel blade
2. Starrett 11H-6-4R (Best Affordable Starret Combination Square)
Starrett combination squares come in many series. One of them which is Starrett 11H-6-4R is another version of Starrett C11H-6-4R above that doesn’t come with satin chrome finish. And thus, if you are looking for an affordable Starrett combination square, Starrett 11H-6-4R should be your choice.
Both of them have a 6″ blade model that means it should be applicable for most of your woodworking work. Besides, they both have a reversible lock bolt, a scriber, and a spirit level. These two squares have blades made of hardened steel. The head of each blade is made of cast iron and has a black wrinkle finish on it. It comes with a clear black on white marking and a 4R graduation scale.
The very small difference is how they look. Starrett 11H-6-4R is more shiny due to lack of satin chrome finish. You may not easily read the graduation when the light is above of your work table as it reflects light. This difference also impact to its price. In addition, the Starrett 11H-6-4R is a lot heavier and cheaper than the Starrett C11H-6-4R.
All in all, the best budget 6-inch combination square is Starrett 11H-6-4R. They are very similar but not exactly the same, with the difference in finish, so you should be careful not to order one for the other. If you like this nice Starrett tool but want something larger, there is the Starrett-11H-12-4R, which is 12 inches long and is a great option for larger layout projects, too.
- Affordable Starrett combination square
- 6 inch blade to cover many jobs
- The regular finish is shinier than the satin chrome finish but it’s not very reflective
3. Starrett C11H-12-4R Combination Square 12″
It is simply the best combination square for 12 inches on our list of the 10 best combination squares. Our favorite combination square is Starrett C11H-6-4R, but if you need something that is as good as our favorite but larger, this is the best choice for you.
The blade is photo-engraved, made of hardened steel, and has a satin-chrome finish. A scriber, spirit level, reversible lock bolt, and a bearing surface that is accurately ground come with it.
- There are useful scales on it.
- Excellent satin chrome finish makes it less light reflective
- Has a good level of contrast
- It is a good choice for larger projects
- It may not fit in your pocket or apron.
- Does not come with a storage case.
4. iGaging 34-212-4 Another Best Affordable 12-inch Combination Square Set
If you need a 12-inch combination square set and you do not want to get charged more money since you do not need very high precision, this iGaging 34-212-4 combination square is for you. You would not put this tool to rugged daily use, so it would last.
When you buy this 12-inch iGaging combination square set, you get a cast iron square head, a satin chrome finished steel blade, a cast iron center-finder head, and a cast iron 180-degree protractor head, all in the same package. It also comes with a spirit level, a hardened scriber, and a padded plastic case for storing it all in.
It is very easy to see the 4R graduation scales permanently etched into the blade of the iGaging 34-212-4, plus it has a good level of contrast.
- Affordable 12-inch combination square set
- It has a satin chrome finish that makes it less shiny.
- It has a good level of contrast.
- You can use it to check the level of your work.
- It has permanently etched markings.
- It comes with a case to store it all in.
- If you use it all the time, it might not last.
5. Starrett C435-12-4R Combination Set (Square, Center, & Protractor)
Combination squares make you more professional and also save you a lot of time because they can measure angles, find the center of objects, and check the squareness of corners with just a single tool, instead of having to pick up and drop several different tools.
There are three heads in this set: a regular square head, a center-finder head, and a protractor head. All of them are made of cast iron and have a black wrinkle finish. On the square head and protractor head, there is a spirit level that is suitable for determining how aligned your work is.
Hardened steel material is used to make the photo-etched blade of this tool. It then gives a nice useful finish with satin chrome. For graduation, it has a 4R style graduation (1/8th, 1/16th, 1/32nd, and 1/64th increments) that is easy to read due to the black on white marking.
Overall, if you looking for the best Starrett combination square set with center and protractor, Starrett C435-12-4R should suit your need. This Made-in-USA combination set has a 12-inch blade length, black wrinkle head finish, satin chrome blade finish, and reversible protractor type. There is another series of Starrett C435-12-4R which is Starrett 435-12-4R. Again, this model doesn’t have a satin chrome finish (only a regular steel finish).
- 4R graduations
- Satin chrome blade finish that makes it not shiny for eye sight
- Black wrinkle head finish
- The reversible protractor type makes angle measurement faster
- You can use it to check the level of your work.
- It comes with a case to store things in.
- The Starrett 435-12-4R combination set version is shiny.
6. Starrett 435ME-300 Metric & Inch Combination Square Set 12″
Usually, woodworkers and carpenters have to choose between the imperial and metric units, which are the two most common units. Sometimes you have to convert between them, and other times you switch back and forth between the two units based on the project at hand. If this is you, then we have the Starrett 435ME-300 combination square that we think will work best for your job. This is a square that gives you the best of both metric and imperial units.
It also comes with the regular square head and two other types of heads: one for finding the center of an object and the other one for measuring angles. In this case, the head is made of cast iron and has a black wrinkle finish, while the blade is made of hardened steel and has a satin chrome finish.
The photo-engraved blade has a length of 300mm (11 3/4 inches) and a very visible black-on-white marking contrast. It has 1/2 mm and 1/32-inch graduation scales on one side of the blade, while the mm and 1/64-inch scales are on the other side.
If you are based in the UK, Canada, Australia, or other countries that use a metric measuring system and looking for a metric combination set, we suggest this Starrett 435ME-300. It comes with imperial (inch) and metric (mm) graduation. If you are searching for best metric combination square, this model could be your favorite.
- Metric and inch graduations
- Best combination square set for UK, Canada, and Australia users
- Satin chrome finish prevents shiny surface that makes you difficult to see the graduations
- It comes with a case.
7. Starrett C33MEH-300 Metric & Inch Combination Square 12″
Buying the Starrett 435ME-300 combination set because it has a dual reading unit could be a complete waste of money because not everyone needs the center finder head and the protractor head. So, if you do not think you need the whole set, this Sarrett C33MEH-300 combination square would be just what you need.
It has a total length of 300 mm, which is about 11 3/4 inches. This combination square is different from the other Starrett combination squares we have looked at. The head of this one is made of forged steel with a smooth black enamel finish, while the blade is made of hardened steel that has been plated with satin chrome.
A reversible lock bolt, scriber, spirit level, and type 3R graduation are some of the things that make this tool easy to use and read.
Another metric-imperial combination square, the Starrett 33MEH-300 can be found for a little less money. If you buy this one, it is made just like the Sarrett C33MEH-300 combination square. The only difference is that it does not have the satin chrome finish like the original.
- For metric users (one of the best metric combination square choices for UK, Canada, and Australia users)
- The blade has a satin chrome finish
- It has a mix of metric and imperial units on it.
- You can clearly see its marking.
- Does not include the storage case.
8. Irwin Tools 1794469 Combination Square 12″ Metric Inch
If you are not a fan of Starrett, or if you do not need the “Starrett quality” for your job, then this is a great 12-inch combination square option for you among the Irwin tools. It is a Chinese-made combination square that has been made to the highest quality possible.
Although it’s cheaper, one of the best things about this tool is very useful etched markings, which means its marking will last for a long time. The tool has a unique die-cast zinc body and a rust-proof stainless-steel blade that will not get rusty. The tool has good contrast and is easy to see and read.
This is a great tool that can be used for larger layout projects and will save you some bucks.
- Etched markings for way better durability of markings
- Cheap but quality
- Die cast zinc body
- Stainless steel blade
- It might not last for heavy-duty job
9. Mr. Pen Combination Square 12″
This is another affordable 12 inch combination square that you can choose from our list of best combination squares. It is a great square tool that should be suitable for construction work, but do not expect it to have high precision or to be very durable. For someone who likes to build things as a hobby or DIY project or fix things but not on a daily basis, this tool is perfect.
The blade of this combination square is made of a durable, rust-proof stainless steel that will not break down. On one side of the blade, there are scales that read 1/8-inch and 1/16-inch, while the other side has mm and 1/32-inch scales.
You can still work even when you do not have a pencil, check the straightness of your work and make sure that your work is correct with this tool because it has a brass scriber, a level, and a spring-loaded brass bolt.
- There are useful scales on it.
- You can use it to check the level of your work.
- It saves money.
- It may not stand heavy-duty use.
10. Johnson Level & Tool 400EM-S 12″ Inch/Metric Combination Square
Johnson Level and Tool is a great company that manufactures great products, and we recommend its 400EM-S combination square. It is good for hobbyists and DIYers who do not do heavy-duty or precise work. Having both metric and imperial units is one of the best things about this tool. It is a very useful tool that could save you money.
Because the combination square is made of a stainless-steel blade and a heavy-duty CNC machined die cast zinc head, it is very durable and resistant to wear. It has a level, a screw-in scriber, and a blade assembly that locks itself when you use it.
There is a lot of contrast in the graduations on this tool, which makes it easy to read. It also has etched markings, so it will last for a long time. This tool is also great for you if you like 1/8-, 1/16-, 1/32-inch, and 1 mm scales.
- Affordable metric inch combination square
- Saves money
- It has etched graduations which will last long
- It may not stand up to daily use.
Things to Consider When Buying Combination Square
This section has more information that you should think about before you purchase your new combination square. For those who are still curious, this section should answer most, if not all, of your questions. For those who are not sure, this section will help you make the right choice.
When you buy your combination square, you should think about the following:
1. The Blade Length
The first thing you need to notice about any combination square is the length. Most of the time, they are between the range of 4″ – 24″ or 150 mm and 600 mm. You should know this before you choose the best one for your job.
Among the best combination squares on our list, the blade lengths are 150 mm, 300 mm, 6 inches, or 12 inches long. These are middle ground squares that would work in most projects, whether you are a professional or a novice. They are also easy to carry around.
Choose the 6-inch combination square if you do not know what length to choose. They should work well for most jobs. They are easy to move around, practical in tight corners, and are good for small and medium projects. There are also 12-inch models that are better for larger projects because they cover more length than the 6-inch models.
Combination squares made of stainless steel or hardened steel blades are a great option. These materials make them resistant to wear and tear. Having a strong and durable steel also means that the blade would last a long time.
The head, on the other hand, is made of many different materials. On our list, we have combination squares made of cast iron, stainless steel, and die cast zinc head. Most of the time, the cast iron head is the most durable of the three materials and the most expensive, while the cast-zinc head is the least durable so it logically follows to purchase a combination square with cast-iron head for an everyday heavy-duty work while a zinc head combination square should be used by DIYers and hobbyist.
3. Reading Unit
Combination squares can come in metric unit, imperial unit, or both. That said, you should keep this in mind when you want to purchase one. If you are woodworkers or metalworkers in the US, it is likely that you work mostly with imperial units and measure in inches, so you should buy an imperial unit square.
It is common for people who live outside of the United States to work with both the metric and imperial units. So, it would be better to buy a tool that comes with both units. This way, you will not have to buy two tools just because you want to have the two units you use the most.
Before you buy a tool, make sure you know what kind of project you are working on, as a metric tool is not the best option for a project in imperial units.
4. Combination Square Set Vs. Combination Square
On our list of the best combination squares above, you could see that some of them are either a whole combo set or just a single combination square. Sets that include all three heads are called “combination sets.” While the combination square has only one head, called the “square head”.
Besides the major difference in how many heads are in each category, the prices for both are not the same. It’s easy to realize that the combination set is more expensive than the combination square.
Here’s what we think: you should only buy the combination set if you need the extra center finder and protractor head. Most of the time, a combination square will work just fine, especially if you buy the best one, which is our overall best Starrett 56362 C11H-6-4r 6-inch combination square or the highly-rated Starrett C11H-12-4R.
If you buy the combination set, don’t forget to figure whether the protractor is reversible or not. The reversible one will make your work easier.
Body Parts and How to Use Combination Square
Do not get dissatisfied with your job or label yourself a lousy handyman simply because your project was damaged due to improper alignment and squareness of the edge of your wood or metal joints. We know you are good, but you may be much better if you spruce up your work with one of our combination squares.
So far, the top producer of combination squares on the market is Starrett. There are more than 100 models produced by Starrett. You could check here.
Keep in mind that the combination square’s squareness is not as accurate as of the machinist square since the stock is slideable. Surely, a solid square is required to provide accurate squareness. In case you are looking for the best precision combination square, there is no like the machinist square does.
Based on our consideration, we pick Starrett C11H-6-4R as the best combination square overall on our list. They would withstand regular wear and tear while maintaining an accurate touch over time.
To check how accurate your combi square is, you can check it with an engineer square. Engineer square is more solid and has less error than combi square.