Our pick for a speed square for marking square and angled cuts: Swanson 7 in. aluminum Speed Square

Swanson 7 in. aluminum Speed Square

Model S0101

Why we picked it

Our pick for marking square and 45-degree lines across a board: Swanson's original 7 in. aluminum speed square, with a lip that hooks the board's edge.

Pro Tool Reviews calls it one of its top 10 go-to tools, usable as a square, miter square, protractor and line scriber.

Bob Vila's research-based guide names it best overall for most users, for its durability and precise markings.

WoodworkNation's guide names it its top pick, for its CNC-machined aluminum body, deep, easy-to-read markings and USA manufacture.

Specs (from the maker)

7 in.; CNC-machined heavy-gauge aluminum (from Swanson's product page)

Square, miter square, protractor, line scriber and saw guide in one (from Swanson's product page)

Comes with Swanson's Blue Book of rafter instructions (from Swanson's product page)

Made in Frankfort, Illinois (from Swanson's product page)

Keep in mind

The Home Depot listing we link is Swanson's S0101-C, the S0101 square sold carded with the Blue Book and a Speed Clip (Swanson lists it as a variant of the S0101); the price is for that set.

Where to buy

More on Swanson 7 in. aluminum Speed Square

Keep in mind

Bob Vila notes the squares occasionally come with a rough finish that you can smooth with a sanding block.
Bob Vila's guide is based on research rather than hands-on testing; Pro Tool Reviews is the hands-on review.

What the sources found

Pro Tool Reviews: Swanson aluminum Speed Squares (external site, opens in a new tab) (independent review, Apr 13, 2022; checked October 25, 2026): Clint DeBoer's review calls the Swanson aluminum Speed Square one of its top 10 go-to framing tools: lighter than the original die-cast models with the same accuracy, usable as a square, miter square, protractor and line scriber, with a diamond cutout for marking seat cuts. We didn't see an affiliate notice on the review page.
Bob Vila: The best speed squares (external site, opens in a new tab) (independent guide, Sep 25, 2026; checked October 25, 2026): Tom Scalisi's guide, based on research, names the Swanson S0101 best overall, for its durability and precise markings, and notes Swanson's patented diamond cutout. The page says it uses affiliate links.
WoodworkNation: The best speed square (external site, opens in a new tab) (independent guide, Apr 6, 2025; updated Oct 17, 2026; checked October 25, 2026): Peter Lynn's guide names the Swanson S0101 its top pick: CNC-machined heavy-gauge aluminum, deep black-filled markings that stay readable, and made in the USA. The page links to stores with Check Current Price buttons; we didn't confirm whether they're affiliate links.
Swanson: Speed Square 7 in. S0101 (external site, opens in a new tab) (maker spec page, no date shown; checked October 25, 2026): Describes a 7 in. CNC-machined heavy-gauge aluminum square that works as five tools in one, comes with the Blue Book and is made in Frankfort, Illinois.

How we picked

We didn't hands-on test these. We picked it by reading an independent review and guides (Pro Tool Reviews, Bob Vila and WoodworkNation), checking Swanson's product page, and checking the price at Home Depot. Every pick has at least three independent sources from at least two different outlets, including at least one independent test or review. They're all linked with the pick, along with what each one found. We also searched the US Consumer Product Safety Commission's recall database on Oct 25, 2026 and found no recall for this square. Prices, review counts and links were last checked on October 25, 2026; prices and stock change, so check the store before you buy.

No paid links. Every link on this page is a plain link: no affiliate codes or tracking, and no company paid or asked to be listed (disclosure). Links open in a new tab.

Some outlets we cite get review samples from tool makers; we don't use pieces a maker paid for or sponsored.