We all remember math class in grade school and being asked to calculate angles for a geometry chapter. Well, while you might not have realized it back then, measuring angles with protractors can be very useful in life. If you’re planning on building a new house to start a family in or you’re getting things ready to add an addition on to your home, mapping out precise measurements with a protractor is a good idea. If you’re an engineer, you know how valuable a tool this can be. So if you have a geometry final coming up or are realizing you should’ve paid attention in that geometry class when you were younger, here are some protractors that could be right for you.

Best Digital Protractor

Taking human error almost completely out of the equation, the GemRed 82305 Digital Protractor Angle Finder helps you pinpoint exactly the angle you need. It is made from stainless steel, so it’s built to last. It is a protractor and ruler combination, so measuring is made super simple. The edges might be sharp, so this is not meant to be used by children. The total length is 400mm and the digital readout is accurate within +/-0.3°. You just rotate the protractor to the desired angle and the digital display will show you what the angle is. You cannot measure reverse angles.

Best Large Protractor Set

Completing your mathematical tools set, you’ll find everything you want in the Mr. Pen 15 Piece Compass Set. With this full set, you’ll receive two metal compasses, one extra lead for graphic compass, one metal divider, two pencils for the compass, one pack of 0.5mm lead, one eraser, one pencil sharpener, one six-inch ruler, one set square that’s 30°/60°, one square that’s 45°, one protractor and another protractor with a swing arm. It comes in a reusable pouch and all of measuring tools show millimeters and centimeters. The swing arm protractor is 6″ long.

Best Small Protractor Set

If you don’t need all that is offered in the Mr. Pen set, then take a look at the Maped Study Geometry 10 Piece Set. Everything is metal, so it won’t bend or flex and break. Packaged in this set are two metal compasses, two triangles, a six-inch ruler, a four-inch protractor, a pencil for the compass, a pencil sharpener, an eraser and a lead refill. This set is equipped to handle a full semester of geometry class and comes in a shatterproof case. The instruments feature both inch and metric gradations.