How to Read a Tape Measure?

What is Tape Measure?

A tape measure also called measuring tape, is a type of flexible ruler used to measure size or distance. Tape measures are made from a variety of materials, including fiberglass, plastic, and cloth. They are among the most common measuring tools used today.

Its design allows for a measure of great length to be easily carried in pocket or toolkit and permits one to measure around curves or corners. Today it is ubiquitous, even appearing in miniature form as a keychain fob or novelty item. Surveyors use tape measures in lengths of over 100 m.

Types of Tape Measure

There are two basic types of tape measures with cases: spring return pocket tape measures and long tape measures. Spring return pocket tape measures will generally fit in a pocket. They are small; the case is up to about three inches across.

The tape is returned to the case by a spring mechanism. Pocket tape measures have a tape 1 to 15 feet (0.30 to 4.57 m) in length and 1⁄4 to 3⁄4 inch (6.4 to 19.1 mm) across. When most people think of a tape measure, they are thinking of the pocket tape measure.

A second tape measure design is what is called the long tape. These are cased tape measures with tapes of 7.6, 15.2, 22.8, 30.4, 60.9, 91.4 and even152.4 meters in length, designed for engineers and builders.

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Because surveying was usually done in rods, surveyors use long tapes of 10.05 meters, and 20.11 meters. Surveyors also used 15.08 meters of a 15.2 meters tape and 30.17 meters of a 30.48 tape measure. Long tapes, instead of being returned by a spring, were usually returned by hand crank.

Tape measures are often designed for specific uses or trades. Tapes may have different scales, be made of different materials, and be of different lengths depending on the intended use. Tape measures that were intended for use in tailoring or dressmaking were made from flexible cloth or plastic.

They are named “sewing tape”. These types of tape measures were mainly used for the measuring of the subject’s waistline. Today, measuring tapes made for sewing are made of fiberglass, which does not tear or stretch as easily.

Measuring tapes designed for carpentry or construction often use a stiff, curved metallic ribbon that can remain stiff and straight when extended but retracts into a coil for convenient storage. This type of tape measure will have a floating tang or hook on the end to aid measuring.

The tang is connected to the tape with loose rivets through oval holes and can move a distance equal to its thickness, to provide both inside and outside measurements that are accurate. A tape measure of 25 or even 100 feet can wind into a relatively small container. The self-marking tape measure allows the user an accurate one-hand measure.

Anatomy of a Tape Measure

Learning how to read a tape measure begins with understanding its different parts.

  • The case is the square-shaped housing for the tape. It is usually plastic or metal and about 3 inches in length.
  • The hook is a bent piece of metal that hooks over the edge of a board or counter. It aids in extending the tape from the case and holding the tape in place for measuring.
  • The hook slot is the hole at the end of the tape. It allows you to latch onto an anchor point such as a protruding nail or screw head.
  • The actual tape or blade is usually yellow or white. It’s the extendable and retractable length of the tool. Most often the blade is made of metal coated in plastic.
  • The thumb lock is a button on the case. When pressed, the thumb lock will hold the extended tape measure to a needed length. Releasing the thumb lock will allow the tape to retract into the case.
  • The belt clip is the fastener on the side of the case. It allows you to hook your tape measure conveniently onto a belt, tool belt or pocket.

How to Read a Tape Measure?

The humble tape measure is the world’s most commonly used measuring tool, accompanying millions of tradesmen and contractors to work every single day.

Whilst the seasoned professionals amongst you will no doubt be fully aware of how to read the various markings on your tape, there will be amateurs, enthusiasts, or those just starting off in their careers who aren’t yet so knowledgeable. We regularly get asked the question “how do you read a tape measure”. In response to our customers, therefore, we’ve put together this simple guide that explains just that!

How to Read a Metric Tape Measure

Above you’ll see a picture of a metric/imperial pocket tape measure. The measurements towards the bottom of the image are metric. In other words, they’re in centimeters and millimeters.

how to read tape measure

There are 10mm in each centimeter (shown by the ten spaces between each cm) and 100cm in each meter. Whilst the centimeters are clearly numbered, to make the blade easier to read the millimeters are not numbered. Also, whilst a few tapes show ‘1m’ to display the 1-meter mark, the majority will show ‘100cm’.

When looking at the image above, the 1st small mark after the 4cm point denotes a measurement of 41mm. The next small mark in line would be 42mm, the next would be 43mm, and so on. 41mm can also be referred to as 4.1cm (0.041m) but the majority of trades in the UK do tend to quote measurements in millimeters.

Step By Step How to Read a Tape Measure

  • Find/read the markings. On a standard tape measure, the biggest marking is the inch mark (which generally has the biggest number, if it has them).
  • As the increments decrease, so does the length of the mark. For example, ½” has a bigger mark than ¼” which has a bigger mark than ⅛”, and so on.
  • Read 1 inch. The space from the largest mark to another is 1 inch.
  • Read one-half inch. Same principle as reading one inch, only this time the space between the second-biggest mark and the biggest is read. You can think of a half-inch mark as half way between a full inch.
  • The remaining markings follow a similar pattern. ¼” is half of ½”. ⅛” is half of ¼”. Most tape measure markings go as small as 1⁄16;”. This tape divides one more time, down to 1⁄32″.

How to Measure Using a Tape Measure?

To use a tape measure, pull the tang out from the housing and hook it on the edge of the object to be measured. Stretch the blade across the object, press the lock, and then observe where the blade meets the end of the object. The nearest line on the blade to the end of the object is the final measurement.

Measure a length. Put the end of the measure at one end of the item or space you want to measure. When the length stops, take a reading on the tape measure.

Find the length. In order to determine the length, you must add the lengths between inches together. For example, the image below has a measurement that goes beyond the space between two-inch marks (that is, one full inch).

In order to find the length, add the length of the inch (1) with the space between the second-inch mark and the third. In this case, you’d add 1 inch + 1/4 inch to get 1¼ inch, or “one and a quarter inch.

For a length less than 1 inch, simply read off the tape measure the length. If the increments of an inch are not labeled, determine the marking’s increment and add together the respective fractions.

As an example, the image below shows a length that goes from the inch mark to an unlabeled marking. We know it’s more than 3/4 of an inch and less than one full inch. The marking is halfway between 3/4 (6/8) and 7/8.

Therefore, the marking is half of 1/8, or 1/16. Taking this knowledge, you simply add the known fractions to find the length. Convert 3/4 to 12/16 for common denominators and add 12/16 + 1/16 to get 13/16 – that’s your length.

How to Read a Tape Measure in Inches

Standard or SAE tape measures clearly show feet, inches, and fractions of inches. The measurements on a tape measure are generally 16 marks to the inch. This means you can measure up to 1/16 of an inch. Some tapes measure from 32 to 64 marks to the inch. Laser distance measurers can often measure accurately within 1/16 inch.

  • When reading a tape measure, find the closest whole inch to the end point. Then examine leftover indicator lines to see what fractions of an inch remain. Add those to the whole inches for your total measurement.
  • To read an inch, look for the large numbers. That number is usually in bold, black type. It’s easy to see and refers to the longest of the markings along the edge. The number of lines between inch marks indicate how precise you can get with your tool.
  • To read 1/2-inch measurements, locate the second-longest mark between the longer inch marks. For 1/4-inch marks, look halfway between the 1/2-inch marks. You can read smaller fractions of an inch the same way. Most tapes will label the fractions to make finding them easier.

How to Read a Tape Measure in Millimeters

Metric tape measures feature 10 marks to the centimeter. The smallest marks on a tape indicate one millimeter or 1/10th of a centimeter. The large, bold markings on a metric tape measure indicate centimeters. The long mark in the center indicates a half-centimeter.

  • To read a metric measuring tape, find the nearest whole centimeter to the end point. Examine the remaining indicator lines to see how many millimeters are left over.
  • Add those to the whole centimeters, using a decimal. For example, say you measure 20 whole centimeters and there are 6-millimeter marks left over. Your total measurement will be 20.6 centimeters.

Special Notes for How to Read Measuring Tape

  • The typical length between studs in a wall is 16 inches on center. This is marked in red on many tape measures.
  • Many tape measures will have 1 foot marks every 12 inches. This eliminates the need to convert inches to feet yourself. Some have special markings every 3 feet as well.
  • Tape measures often use small, black diamond or triangle shapes called black truss marks. They indicate truss layouts of every 19 3/16 inches. This spacing is often used by some engineered joist manufacturers. There are 5 of these marks for every 8 feet.

Tape Measure Tips

  • A properly functioning hook will move slightly. It is designed to slide based on the thickness of the metal, usually about 1/16-inch. This allows the tape to give an accurate inside and outside measurement.
  • Standard tape measures usually go from 15 to 50 feet. Long tape measures come in greater lengths of 100 feet or more. They are often made of flat steel or fiberglass and retract with a hand crank. Self-retracting tape measures are flexible and can be bent to measure into tight spaces or around corners.
  • Use a screw or nail as an anchor point to fix the end of your tape measure in place.
  • To draw a perfect circle, anchor the tape measure’s hook slot onto an anchor point. Engage the thumb lock. Hold a pencil or other writing utensil down flush with your tape measure. Turn 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, retract the tape back in slowly.
  • If the hook on your tape measure is bent or damaged, you’ll get inaccurate measurements. A bent hook can often be adjusted with two pair of pliers. Or tap it with a hammer against a hard surface.
  • If you’re using multiple tapes on the same job, calibrate them to any one of several good rulers and yardsticks available. Tapes can be brought into agreement by slightly bending the hooks until measurements match.

Reading a tape measure is a skill you can easily master. Using this small, sturdy hand tool can improve the accuracy of your project measurements. Learning how to use a tape measure properly means to always “measure twice, cut once.” You can use a standard tape measure or opt for a metric one.