Mastering Tape Measure Math & Fractions
Stop struggling with adding sixteenths and eighths in your head. Use our precision tape measure calculator for flawless woodworking.
The Problem with Fractions
Measure twice, cut once. It's the golden rule of woodworking, but it's hard to follow if the math is wrong. Adding 7 5/16" to 12 7/8" while standing at a miter saw is where mistakes happen.
How to Read a Tape Measure
Most US tape measures are divided into 1/16th inch increments.
- The longest lines are the Whole Inches.
- The next longest are the Half Inches.
- Then Quarters, Eighths, and finally Sixteenths.
The Tape Measure Calculator
Our tool below works exactly like your tape measure. Enter your feet, inches, and fractions to get a perfect result every time.
Practical Woodworking Tip
When you need to subtract a 'blade kerf' (the thickness of the saw blade, usually 1/8"), you can use this calculator to adjust your measurements perfectly.
Common Decimal Conversions
- 1/4" = 0.25
- 1/2" = 0.50
- 3/4" = 0.75
- 1/8" = 0.125
Industry data feed active. Integrated sponsor slots reserved for verified partners.
Support the Blueprint
DIYLookup is built for builders by builders. Help us keep the math open-source and the site ad-free by supporting our mission.