Protractors & Squares

Protractors and squares help tradespeople, machinists, inspectors, woodworkers, fabricators, and maintenance teams measure, mark, set, and check angles. Common commercial uses include woodworking and construction layout, workpiece marking, machine setup, pipe and cylindrical-object layout, alignment, and inspection.

Product Display:
Helpful Buying Guide

Choose protractors and squares for the way you measure and mark

This category includes traditional squares for right-angle layout, adjustable combination squares, manual bevel protractors, magnetic dial tools, and digital instruments. Start with the angle or measurement task, then compare blade reach, reading style, surface compatibility, graduation detail, and features that support positioning or marking.

Visual Guide

Popular examples in this category

Use Cases

Match the tool to the measurement task

Use carpenter's squares for everyday measuring and layout, combination squares for adjustable 45° and 90° checks, and bevel protractors for setting and measuring angles. Digital tools provide electronic angle or level readings for setup, alignment, and inspection.

How to Choose

Compare reach, readings, and adjustment

Consider whether you need a fixed square, an adjustable head, interchangeable 6 in. and 12 in. blades, or a longer 12 in. or 24 in. blade. For detailed work, compare graduation formats, vernier or dial readings, and digital resolution.

Applications

Support work in the shop or field

Represented applications include woodworking, construction, machining, inspection, fabrication, maintenance, pipefitting, and general layout. Magnetic features can help position compatible tools on metal surfaces, while V-openings support contact on round work.

Additional Info

Look for useful handling features

Depending on the tool, available features include LCD or invertible displays, locking clamps, zero and hold functions, scribers, spirit levels, reference tables, protective finishes, and fitted or padded storage cases.

360°Measuring range

Available on the electronic protractor for full-rotation angle measurement.

0.05°Digital resolution

Provided by the electronic protractor for detailed angle readings.

16 x 24 in.Carpenter's square size

Represented in both aluminum and steel carpenter's squares.

1/64 in.Fine graduation increment

Included within the 4R graduation format on select combination squares.

Comparison Guide

Compare the represented tool types

Use this overview to narrow the category by task and the features most relevant to your work.

Tool typeBest suited forRepresented features to compare
Carpenter's and bench squaresGeneral layout, marking, woodworking, and angle checksFixed square formats; common angle markings; engraved or embossed graduations; reference tables or angle-marking holes
Combination squaresAdjustable layout, 45° and 90° checking, and measured markingAdjustable locking heads; 4R graduations; 6 in., 12 in., or 24 in. blades; select spirit levels and scribers
Bevel and dial protractorsAngle measurement, setup, alignment, and inspectionDial or vernier readings; magnifiers; 6 in. and 12 in. blades; locking clamps; angle attachments
Magnetic and electronic angle toolsMetal-surface positioning, alignment, level checks, and digital angle readingsMagnets; LCD or invertible displays; zero and hold functions; V-opening; center punch; rechargeable power on select tools
Planning Guide

Plan the right fit before choosing

Tool Types

Select a square or protractor based on your primary work

Squares are suited to measuring, marking, and checking common angles, while protractors focus on measuring and setting a broader range of angles. Digital level sensors and electronic protractors add electronic displays for quick reference.

  • Carpenter's squares provide 16 in. x 24 in. formats for measuring and layout work.
  • Combination squares offer adjustable heads and 45° and 90° faces for common square and miter checks.
  • Bevel protractors use dial or vernier scales for detailed angle measurement and setup.
  • Magnetic dial protractors support positioning on applicable metal surfaces and work with piping or other cylindrical objects.
  • Electronic tools offer functions such as zero, hold, invertible displays, and full-rotation measurement.
Measurement and Layout

Compare reading styles and marking capabilities

Choose a reading system that fits the level of detail and the working position required. Some tools provide fractional-inch graduations for layout, while others provide dial, vernier, or digital angle readings.

  • 4R graduations offer 1/8, 1/16, 1/32, and 1/64-inch markings.
  • One dial-reading bevel protractor has 1° dial graduations and 5-minute vernier graduations.
  • A digital protractor provides 0.05° resolution and a 360° measuring range.
  • Bench squares include laser-engraved graduations, angle-marking holes, and offset blade positioning.
  • A magnetic dial protractor includes a center punch for precise layout marking.
Size, Materials, and Storage

Plan around workpiece size and working conditions

Tool length and construction can affect how a tool fits the work. The represented range includes compact 3 in. and 6 in. bench squares, 6 in. and 12 in. protractor blades, and 12 in. or 24 in. combination-square blades.

  • Interchangeable 6 in. and 12 in. blades accommodate different workpiece sizes.
  • 24 in. combination-square blades provide reach for longer or larger workpieces.
  • Aluminum, hardened steel, stainless steel, cast iron, and anodized aluminum constructions are represented.
  • Protective finishes help resist corrosion, rust, or scratching on select tools.
  • Cases are included with select protractors and combination squares for storage or transport.
FAQ

Common questions before buying

What is the difference between a carpenter's square and a combination square?

Carpenter's squares provide a fixed format for measuring and layout. Combination squares use an adjustable head along a blade and include 45° and 90° faces.

Which tools can measure angles beyond common square or miter angles?

Bevel protractors, magnetic dial protractors, and electronic protractors are designed for angle measurement. The electronic protractor has a 360° measuring range.

Are magnetic options available?

Yes. The digital level sensor, magnetic dial protractor, and electronic protractor include magnetic features for compatible metal surfaces.

What blade lengths are represented for precision measurement tools?

Represented options include 6 in. and 12 in. interchangeable protractor blades and 12 in. or 24 in. combination-square blades.