It’s fair to say that even the most casual weekend woodworker has a few combination squares sitting around their workshop. That’s because this functional square is a workhorse that does the job of several specialty tools.
But what’s the best combination square for your needs? Our detailed buying guide covers the essentials, including our top picks and helpful insights, so you buy the right tool the first time. Read on for more information.
DIY Gear Reviews’ best combination squares:
- iGaging 6-Inch 4r — Best 6-inch combination square
- iGaging 12-Inch 4r — Best 12-inch combination square
- Irwin 6-Inch and 12-Inch Set — Best combination square set
- Johnson Level & Tool 400 EM-S 12-inch — Best budget 12-inch combination square
- Swanson TC130 6-Inch — Best budget 6-inch combination square
- WorkPro Rafter and Combination Square Set — Best combination square and speed square set
Combination squares at a glance
| Product | Scale | Graduations | Markings |
| iGaging 6-Inch 4r | Imperial | Up to 1/64″ | Etched |
| iGaging 12-Inch 4r | Imperial | Up to 1/64″ | Etched |
| Irwin 6-Inch and 12-Inch Set | Imperial & metric | Up to 1/32″ | Etched |
| Johnson 400 EM-S 12-Inch | Imperial & metric | Up to 1/32″ | Stamped |
| Swanson TC130 6-Inch | Imperial & metric | Up to 1/32″ | Etched |
| Workpro set | Imperial & metric | Up to 1/32″ | Etched |
- Up to 1/64” scale
- Includes a great carrying case
- Imperial-only rule
iGaging is a relatively unheard of brand, but it should be on your radar if you’re seeking a high-end tool without breaking the bank. The iGaging 6-inch 4r’s build quality matches what would otherwise cost double with a different high-end brand. Importantly, the square is built with high tolerances for squareness with an accuracy of 0.005″ per 12 inches. The satin chrome precision steel blade packs in an array of etched graduations up to 1/64″. We also appreciate that the product comes packaged in a fitted plastic case and has one of the most useful scratch awls among our picks.
- Up to 1/64” scale
- Includes a great carrying case
- Imperial-only rule
iGaging offers a standalone 12-inch square with the same features as the 6-inch 4r model on this list. This precision tool comes in handy for checking square and striking 45 and 90 degree angles on bigger work pieces.
- Great build quality and price
- Imperial and metric rule
- Up to 1/32" scale
- Blade sliding mechanism isn't extra smooth
This set is a great pick for beginner woodworkers wanting to build out their tool collection on the cheap. It’s hard to beat the build quality, price, and precision of this set. The array of etched markings means this set can strike precise imperial or metric measurements with the durability to last years. Each square also includes a single bubble level and an adjustable knob to lock in the blade. What stands out most is this model’s scratch awl. The awl is pressure fitted and slides out fast, whereas all other picks on this list are threaded and must be twisted out.
Upgrade pick: iGaging 6-Inch and 12-Inch Set. The set includes the same 6-inch and 12-inch models that are picks on this list. This is the pick to go with if you’re looking for a set with rulers with graduations up to 1/64″.
- Imperial and metric rule
- Smooth sliding rule
- Up to 1/32” scale
- Dual measurement scales take some getting used to when marking lines
If you’re looking to get the best bang for your buck, then consider the Johnson Level & Tool 400 EM-S 12-Inch combination square. The one thing that concerns us with products at this price range is whether they’re accurate or not. There’s no concern with this model — both the 45 degree and 90 degree angles and the ruler are accurate. This square also has a ruler with both imperial (up to 1/32″ graduations) and metric scales. The major downside is that the ruler has stamped markings on the ruler. Etched graduations are great for durability. That said, you’re sure to get many years of rugged use out of this tool. This model scored highest in our testing for the smoothest ruler slide and adjustable knob quality.
- Imperial and metric
- Up to 1/32" scale
- Etched blade markings
- Accuracy
- Scratch awl can be finicky to remove
Swanson is synonymous with squares. It’s easy to understand why with the Swanson TC130 6-inch combination square. We think it’s one of the best budget combination squares available. The etched black graduations are precise and run up to 1/32″. Swanson also offers a lineup of combination squares, including a 12-inch version (comes in either a metal body style or its Speedlite plastic body style) and a 16-inch version. The adjustable ruler is among the best on our list with a smooth glide that can only be matched by the Johnson Level & Tool model.
- Imperial and metric
- Up to 1/32" scale
- Etched blade markings
- Lightweight build quality doesn't feel premium
The WorkPro Rafter and Combination Square Set is the perfect choice for woodworkers wanting both a combination square and a speed square. The 12-inch combination square has an etched ruler with imperial graduations that run up to 1/32″ and a metric scale. The 7-inch rafter (or speed) square also comes in handy for added versatility, both in the woodshop and around the home for other DIY projects.
Why do you need a combination square?
A combination square can be purchased on the cheap and is one of the most versatile tools in your shop. Some of the most common jobs they can help you accomplish are checking for square, striking 90 degree and 45 degree lines, scribing lines for rip cuts and joinery, measuring material thickness, adjusting tool heights, and setting saw blades at 90 degree angles.
Features of the best combination squares
Combination squares all share a few common elements, including a base that can strike both 90 degree and 45 degree lines, a removable scratch awl, and an adjustable knob to lock in the included ruler’s length. Some combination squares will also include a bubble level.
But the best option is the one that does the tools most important job: measuring for square.
Beyond squareness, build quality is the next most important factor. We suggest staying with metal tools versus cheaper plastic options available in the market. There are already many great metal options available for any budget, so the tradeoff of picking plastic to save a buck or two doesn’t make sense.
You’ll also want to pick a combination square with etched ruler graduations if you put your tools through the ringer and want them to last a long time. The alternative is a ruler with stamped graduations. Stamped isn’t bad, but it won’t last through decades of rugged use.
Lastly, we think the best models should offer great build quality for a good price. There’s not much sense spending money on the most expensive options when you can get the same quality for half the price. You can get a quality combination square for $10 to $20 and heirloom quality for $30 to $50.
The highest price squares run upwards of $100. No doubt you’ll appreciate the quality if one is gifted to you. But paying such a steep brand tax doesn’t get you much more than the premium picks we’ve included on this list.
How to pick the best combination square
Picking the right combination squares comes down to three things.
First, ask yourself what size projects you’ll be working on. Striking lines and measuring for square on big work pieces like cabinetry and furniture are best suited for a 12-inch square. Doing the same on smaller work pieces like small boxes and drawers is better suited for a 6-inch square.
The reality is many woodworkers will find their projects vary in size. So, a good starting point would be to just buy both a 6-inch and a 12-inch combination square from the same brand hand tool brand.
Next, determine if you’ll need a ruler with an imperial or metric scale. Some combination squares include both. But keep in mind that the rulers on these squares tend to include an imperial scale on the bottom of the ruler and metric on the top, not one side with imperial and the other side with metric measurements. This just means you may need to fiddle with the tools orientation a few times on your workpiece to use the intended measurement.
Lastly, pick your price range. You can get a quality tool for under $20 or spend $30 to $50 to get heirloom quality.
Who makes the best combination square?
Our testing found that iGaging makes the best combination squares for the money. Importantly, iGaging’s combination squares are built with tolerances that are higher than what you’d need for the finest woodworking. For example, iGaging’s combination square head’s squareness are built to a tolerance of 0.005″ accuracy per 12 inches.
Brands like Woodpeckers and Starret are common picks when searching the market for the best options.
But is a pricey Starret combination square worth it? There’s no doubt that high-end brands like Starret make great tools. But the brand tax you pay with these products isn’t worth the additional cost for most woodworkers. iGaging brand squares can be found for half the cost of a Starret model, and both have similar tolerances needed for fine woodworking.
How we tested the picks
We first researched the market to find the most popular woodworking squares. We found 17 models worth digging deeper on. We then reviewed online ratings and chat forums for opinions on these tools. That research then resulted in our shortlist of six products that we purchased to test in-house. Our testing consisted of checking for 90 degree, 45 degree, and ruler accuracy, in addition to inspecting each tool’s build quality. Build quality inspections consisted of reviewing the quality of the adjustable knob, the glide smoothness for the ruler, and the scratch awls ease of removal and insertion.