Irwin Combination Square Review

Irwin combination square hero image

Quick Take

The Irwin Combination Square is an easy-to-recommend pick for beginner woodworkers wanting to build out their tool collection cheaply. It’s hard to beat the build quality and price combination at this price point.

Irwin 6-Inch and 12-Inch Set
  • Great build quality and price
  • Imperial and metric rule
  • Up to 1/32" scale
  • Blade sliding mechanism isn't extra smooth
Check Price
Models tested: We tested the Irwin 6-inch Combination Square and the Irwin 12-inch Combination Square. Both can be purchased separately or as a set. Other sizes available: Irwin 16-inch Combination Square

Alternative to consider

If you want a premium combination square with graduations down to 1/64”: The iGaging Combination Square Set includes both a 6-inch and a 12-inch combination square. These squares also have a premium build quality with a rule with 1/64” graduations.

Features overview

The Irwin Combination Square includes most of the standard items you’d find on a combination square. But where it has some extra versatility is on the rule.   The rule includes both an imperial and metric scale and is 1/16” thick. One side of the stainless-steel blade includes inches with 1/8” graduations on one edge and 1/16” graduations on the other edge. The other side of the blade includes inches with graduations moving down to 1/32” on one edge and centimeters and millimeters on the other edge. RELATED >> How to use a combination square Importantly, the rule also has etched markings, making it far more durable than the best combination squares with stamped markings. The anvil is made of cast zinc that is CNC milled for accuracy on the 45-degree and 90-degree edges. The metal body also includes a single bubble level.
The 12″ model taken apart. Credit: Nathan Hamilton
35A80748 76E2 4C3B 9498 8BABA2C38A25
The 6″ model taken apart. Credit: Nathan Hamilton
Finally, and not to be overlooked, the Irwin Combination Square’s scratch awl at the base of the anvil is our favorite out of all the combination squares we tested. The scratch awl is removed and inserted by sliding it in or out, not twisting it like most combination squares on the market. The scratch awl also seats easily back into its holding place, which can help for efficiency around the shop.

Build quality

Compared to other metal combination squares, the Irwin Combination Square stands out. But don’t expect to buy one expecting premium-priced build quality that you’ll brag to your friends about. This isn’t to say that any of the Irwin Combination Squares are of poor quality. In fact, they are good to great quality for their price point. This assessment is mostly related to the fact that the Irwin Combination Square’s rule isn’t as smooth as other combination squares we tested around this price point. Otherwise, the fit and finish are great, and the adjustable knob is smooth turning. And as we mentioned, the rule has etched markings that should withstand years of heavy-duty use.


The 6-inch Irwin Combination Square can be found readily online for less than $10. The 12-inch Irwin Combination Square is commonly priced a few dollars higher, and the 16-inch Irwin Combination Square is below $20. Accordingly, you won’t break the bank, even if you pick up a few to keep around the shop. Most importantly, the Irwin Combination Squares pack in all the essentials with the cherry on top is that our tested models were square out of the box. The combination of features and accuracy means beginners (and perhaps even advanced woodworkers) will find these easy pick-ups to be valuable woodworking squares.


  • Are Irwin Combination Squares accurate?

    We tested the 6-inch and 12-inch Irwin Combination Squares and found that both were accurate out of the box. The rules were tested to 1/32” accuracy against a reference rule. The anvil’s accuracy for 45-degree and 90-degree lines was tested to a tolerance of 1/32” for every foot.

  • Are Irwin Combination Squares made in the USA?

    Most Irwin Tools are manufactured in China.

  • Does Irwin offer a warranty for its squares?

    Yes, Irwin’s hand tools have a lifetime warranty that protects against defects in material and workmanship under normal wear and tear circumstances. An Irwin tool can be returned to the place of purchase for a replacement.

Picture of Nathan Hamilton
Nathan Hamilton
Nathan Hamilton is the founder of DIY Gear Reviews and a recognized expert in the home and DIY space. He has over 200 bylines covering topics such as power tools, hand tools, and woodworking. Nathan is the strategic director for DIY Gear Reviews, deciding everything from the content covered to designing the testing methodologies for lab-tested reviews. He can be emailed at


Leave a Comment