Buying Guide

How to Use a Tape Measure

Anatomy of a Tape Measure
Two tape measures resting on a board.
  • Thumb lock – press the thumb lock down to hold the tape measure at the length it’s extended and prevent it from retracting into the case
  • Hook slot – a hole at the end of the tape that allows you to latch onto an anchor point 
  • Tape – the ruler part of the tape measure that identifies measurements 
  • Belt clip – allows you to hook your tape measure conveniently onto a belt, tool belt or pocket 
  • Case length – the square-shaped case around the tape, usually around three inches in length


How to Read a Tape Measure
Close up of measurement points on a tape measure.

There are tape measures for general use and also specialized measuring tapes that are marked for truss lengths and stud intervals. Standard tape measures are available in metric units and imperial units. 


The typical length between studs in a wall is 16 inches. This is marked in red on many tape measures.


Many tape measures will have foot marks designated, eliminating the need to convert inches to feet yourself.


The number of lines between inch marks indicate the precision to which you can measure.


In the case of imperial units, there are generally 16 marks to the inch, meaning you can measure up to 1/16 of an inch. This level of precision is rare in common DIY measurements, but there are some measuring tools that measure 32 or 64 marks to the inch.  

  • To measure, lay the tape along the length you’re measuring, and mark the spot where the tape lines up with the edge.
  • Find the closest whole inch to the end point, then examine leftover indicator lines to see what fractions of an inch are left over. Add those the whole inches and this will be your total measurement.

Metric units are even easier to calculate. There are 10 marks to the centimeter. The long mark in the center indicates a half-centimeter. The smaller marks indicate 1/10 of a centimeter, also called a millimeter.

  • To measure, find the nearest whole centimeter to the end point, then examine leftover indicator lines to see how many millimeters are left over. 
  • Add those to the whole centimeters, expressed as decimal. For example, if you measure 20 whole centimeters and there are 6 millimeter marks left over, your measurement will be 20.6 centimeters.

Tip: Be sure to measure to the indicator lines themselves, not the numerals on the tape.

Learn More
Tape measure head anchored to a point for stability.
  • When measuring a length that backs you into a corner, add the length of the tape measure case to the tape measure’s reading – most tape measures have a 3-inch case.
  • Self-retracting tape measures are flexible and can be kinked to measure into tight spaces or around corners.
  • An anchor point is a screw or nail that allows you to anchor the end of your tape measure. 
  • To draw a perfect circle, anchor the tape measure’s hook slot onto an anchor point, engage the thumb lock, and holding a pencil down flush with your tape measure, pull it in a circle around the anchor point.
  • Be careful when retracting a tape measure. Allowing it to snap back can damage the tape and possibly give you a cut. Instead, roll the tape back in slowly.
Get Inspired
A woman measuring a project with a tape measure.

Now that you know how to use a tape measure, let’s tackle some projects:


Add a good, sturdy measuring tape to your tool belt and learn how to read a measuring tape accurately, and you'll be amazed at how that small hand tool can improve the ease with which you tackle your projects. You can consult our other guides on how to use tools effectively, including how to use a power drill, how to use a circular saw and how to use a nail gun.