Learn More About Tape Measures


You use it all the time, but you probably don’t know much about how your tape measure is made. After all, you use it to make other things. Why would you bother learning the fine details?

It’s time to give the tape measure its due! Let’s dive into the anatomy, the names of each piece, and some of the secret features you may have never heard about.

What Are the Different Parts of a Tape Measure?

The tape measure is made of a bunch of different pieces. These parts can be metal or plastic and include:

  • Case
  • Case Length
  • Spring and Stop
  • Thumb Lock
  • Blade/Tape
  • Hook
  • Hook Slot
  • Belt Clip


The case is like the house for the tape where it lives all nice and cozy. The most durable models are made from metal, while plastic is more affordable.

Case Length

Many tape measures come with the case’s length printed on the back. This number comes in handy when you’re measuring around corners as you simply add it to your straight across dimensions.

Thumb Lock

You can stop your tape measure from automatically retracting by pressing the thumb lock down. Push it back up when it’s time to put that tape measure away.


The tape, also known as the blade, is what you use to get your measurement. Most tapes feature imperial units (inches) on the top row and metric units (centimeters) on the bottom.


If you’ve ever measured a table or other hard surface, you’ve likely used the hook at the end of the tape. This metal piece is loose on purpose since the first inch is 1/16th of an inch short, meaning it needs to be pulled taut to ensure accuracy.

Hook Slot

A donut hole may be there for decoration, but that’s not the case with the hook slot. It’s actually designed to hook onto a nail or screw, which can come in handy during construction projects.

Belt Clip

Your tape measure won’t fit on your tool belt or pants pocket without the belt clip. It’s the only way to look stylish and official!

A tape measure wouldn’t quite work the same if any of these pieces were missing. Each part is designed to bring you accuracy and functionality!

The Science Channel has more to say about how your tape measure works!

How Do You Read a Tape Measure?

In order to read a tape measure properly, you need to know the difference between metric and imperial. It also helps to try and remember that math lesson from third grade.

First things first, let’s talk about what all of those symbols and lines mean!

  1. #1: The top row of numbers are your imperial measurements.
  2. #2: The bottom row of numbers are your metric measurements.
  3. #3: The line that hits the blade right before the “1” is a ½ inch.
  4. #4: The blade indicates zero inches or centimeters.
  5. #5: Every number on the top represents a whole inch.
  6. #6: The dashes in between each number on the top are 1/16th of an inch.
  7. #7: Every number on the bottom represents a centimeter.
  8. #8: The dashes in between each number on the bottom represents 1 millimeter. There are 10 total between each centimeter.

Is this making your head spin? It’s time for a quick fraction and conversion lesson. Your math teacher was on to something when they said this information would come in handy!

Now that you know what each line represents, and you’re more familiar with the math of it all, you should be able to get a full idea of what you just measured. Be sure to include every dash in your final total and don’t forget to double check your work!

What Are the Secret Features of Your Tape Measure?

You already know that your tape measure is good for figuring out length, width, and height. It turns out, though, there are some other hidden tricks that may come in handy during your next project!

Scribing Tool

Most tape measures have a serrated edge. You can use this to scratch a mark into a surface if you don’t have a pencil handy.

Black Diamonds

You’ll see a black diamond on some measuring tapes. These are spaced a little more than 19 inches apart and are meant for construction workers as they mark the standard spacing of trusses when building a roof.

Roman Numerals

You will sometimes see Roman numerals on a tape measure. These refer to different classes, with I indicating a more accurate measurement and III being the least. Most tape measures are designed as Class 1 or 2.

Flipped Hook

In some cases, it might be more practical to measure from above instead. That’s the beauty of the flipped hook on the end of most tape measures!

Manufacturing Year

Go ahead and ignore that M number at the bottom of your tape. It’s simply listing the year that particular tape measure was manufactured.

Arrows or Stud

Every 16 inches,  you may see a double arrow, a number marked in red, or the word “STUD.” This helps you locate every stud that may run across a wall once you’ve located the first one.

CE Mark

Does your tape measure feature a “CE” mark? That means it conforms to European Union regulations. It’s not really an indicator of quality, but more so of the measurements set forth at a national level in Europe.

Testing Body

This four digit number, which is usually 0126, relates to the agency responsible for certifying the tape measure – the National Weights & Measures Laboratory in Middlesex.

Why is Measuring Important?

Imagine buying a floor rug for your living room that doesn’t quite fit under the coffee table or a new bed for your apartment that you can’t get through the door frame. It’s in moments like these that a good tape measure is a lifesaver!

Of course, those are only minor mishaps in the grand scheme of things. There have been far worse measuring blunders throughout history!

The Bottom Line

Now you know a little bit more about how that tape measure works and why it matters. This tool is often overlooked, but just as important as that hammer and drill. Give it a little bit of appreciation during your next project!


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About the author

Alyssa Mertes

Alyssa is a promo expert with over four years of experience in the industry. She is the Lead Copywriter at Quality Logo Products and has had work published for the Promotional Products Association International and the Advertising Specialty Institute.