As a woodworker, I’m obsessed with measurement accuracy. I once froze a 25-foot steel tape measure and baked another one to see if they’d still read the same. They came within a sixteenth of an inch of each other before and after, and it didn’t seem to matter that I’d shelled out $20 for one and a mere $5.95 for the other.
The lesson here is that whether measuring lengths, distances, diameters, or angles, modern measuring tools can be trusted. The usual cause of mismeasurement is the person measuring—you have to choose the right tool for the task and know how to use it correctly.
In this article, you’ll find our top picks for basic household measuring, plus a few specialized tools for extra-big and super-small jobs. If, like me, you worry about the veracity of your measurements, you can opt for electronic tools, which minimize human error. Even This Old House general contractor Tom Silva, a digital skeptic from way back, has been won over—sort of—by his sonic measuring tool. “I’m always surprised by how accurate it is,” he says. “I check it with a tape every time.”
Dial Caliper
Best for: Measuring small distances, such as the outside and inside diameters of pipes, screws, and drill bits.
Look for: A 6-inch caliper, which can handle most household needs, with a dial readout that gives measurement in sixty-fourths or hundredths of an inch.
Our favorite: General Tools 142 Plastic Dial Caliper; about $24
Folding Rule
Best for: Measurements inside door and window frames, bookcases, cabinets, and other built-ins.
Look for: A 6-inch metal slide, the most reliable way to get an accurate inside measure. After you’ve unfolded as many segments of the rule as you can, extend the slide and add on its measurement.
Our favorite: Klein Tools 910-6 Folding Ruler; about $22
Metal Rule
Best for: Measuring and cutting roll and sheet materials, such as wallpaper, glass, and plastic.
Look for: A rigid, thick metal rule, which makes a great straightedge when cutting materials.
Our favorite: Victor Easy Read Stainless Steel Ruler; about $9
Digital Tape Measure
Best for: General measuring without the hassle of reading fractions.
Look for: A tape that can convert fractions to decimals and compensates for the size of the tape case on an inside measure.
Our favorite: BOSCH GLM100-23 100 Ft Blaze Laser Distance Measure; about $40
Tape Measure
Best for: General measuring.
Look for: A 25-foot or longer tape that’s at least 1 inch wide so it can extend without bending, and/or a narrow 10-foot tape, which fits easily in a pocket; fractions and feet clearly marked; 16-inch intervals (stud centers) noted in color or bold type.
Our favorite: Komelon SL2825 Self Lock 25-Foot Power Tape; about $9
Rafter Square
Best for: Measuring angles on rafter pitches, stair slopes, and miters.
Look for: An aluminum square with markings for angles as well as roof pitch.
Our favorite: IRWIN Tools Rafter Square; about $14
Electronic Protractor
Best for: Measuring and copying angles.
Look for: An adjustable tool that can determine an angle to 0.1 degree; digital readout; calculator that can figure miter-saw settings for crown molding.
Our favorite: TBVHOMM Digital Angle Finder Protractor; about $150
Sonic Measure
Best for: Measuring rooms and interior spaces up to 50 feet across.
Look for: A tool with a laser pointer so you can see exactly where you’re measuring, with accuracy to 1% or better.
Our favorite: Wintact Digital Ultrasonic Thickness Gauge Tester Meter; about $160
100-Foot Tape Measure
Best for: Measuring long distances, as in foundations, house exteriors, and garden plots.
Look for: A durable fiberglass or steel tape.
Our favorite: DeWalt 100-foot tape measure; about $23
Walking Wheel
Best for: Long exterior measurements, such as lot boundaries or driveway layout.
Look for: A wheel with a 12-inch diameter or more, plus an odometer-style or electronic counter that goes up to 10,000 feet and subtracts when wheeled backward. Bonus points if it has a kickstand.
Our favorite: Zozen Measuring Wheel; about $40