When it comes to systems of measurement, the UK is in a unique position as we have officially adopted the metric system (apart from road signs, which still use miles), though it is still common to see and hear both imperial and metric measurements used in day-to-day life.
While this means that many people are able to understand and conceive measurements in both the imperial and metric systems, it can cause some confusion if you are required to take a measurement or use a piece of equipment that does not have the system you are familiar with.
Many tape measures in the UK have markings that delineate millimeters, centimeters, and meters on one side, and inches, feet, and fractions of inches, on the other. However, there are some that only offer readings in one measurement system, which can be frustrating if you don't know how to convert or read such measurements.
We are going to look at how to read tape measures with both systems of measurement, find out how to convert from one to the other, and show you how to use your tape measure properly.
Tape measures have clear markings for either centimeters, inches, or both. They may also have meter and feet markings, and the small lines dividing the inches or centimeters represent millimeters or fractions of inches, though the values of these are usually not written on the tape.
There are three main types of tape measures: self-retracting metallic tape measures, manually reeled tape measures, and plastic tape measures. We will explore the uses of each in greater detail later.
But let's start by finding out how to read metric tape measurements.
A metric tape measure is any tape measure that uses millimeters, centimeters, and meters.
On a metric tape measure, the centimeters are usually clearly numbered, and there may be meter marks along the tape as well. Most metric tapes delineate millimeters with small lines but do not write the millimeter values above them. Therefore, you need to know the following:
- 10 millimeters = 1 centimeter
- 100 centimeters = 1 meter
- 1,000 millimeters = 1 meter
When you use a metric tape to measure, you have a choice of how to write the measurement. For example, the following measurements are all equal to one another:
- 5.7 centimeters
- 57 millimeters
- 0.057 meters
So which should you choose?
Unfortunately, the frustrating answer is that it depends.
You should use whichever measurement seems most appropriate for the item you are measuring. For example, if you are measuring a room, meters would be the obvious choice as the room is likely to be a few meters wide and long and, therefore, thousands of millimeters. However, if you are measuring the width of a plant stem to track its growth, millimeters are probably going to be best.
An imperial tape measure uses inches and foot measurements. It will usually have large markings for every inch, with the foot measurements also written, but in a different typeface to the inches - often emboldened in red or black.
- 1 foot = 12 inches
Between the inch marks, there should be shorter lines that represent fractions of an inch. The line in the middle of two inch marks represents the half inch marking, and it is usually emboldened. Then there should be quarter, eighth, and sixteenth lines as well.
Again, if you have taken your measurements in inches and feet, you may be wondering which you should choose. The following measurements are equal to each other:
- 14 inches
- 1 foot 2 inches
So which is best?
Well, once more, the choice is yours. Using inches keeps the measurement in one unit, which makes it easier to compare and convert. However, feet may be appropriate for longer measurements.
If you need to convert millimeters, centimeters, meters, inches, or feet, you need to know the following conversion values:
- 1 meter = 100 centimeters
- 1 centimeter = 10 millimeters
- 1 meter/100 centimeters/1,000 millimeters = 3.28 feet
- 1 centimeter/0.1 meters/10 millimeters = 0.3937 inches
- 1 foot = 30.48 centimeters/0.3048 meters/304.8 millimeters
- 1 foot = 12 inches
- 1 inch = 2.54 centimeters/0.0254 meters/25.4 millimeters.
- 1 inch = 0.0833 feet
There are 30.48 centimeters in one foot. So you should perform the following equation to convert foot measurements to centimeters/meters/millimeters:
- centimeter = feet x 30.48
- meter = feet x 0.3048
- millimeter = feet x 304.8
There are 3.28 feet in one meter. So you should perform the following equation to convert measurements to centimeters/meters/millimeters to feet:
- feet = centimeter x 0.0328
- feet = meter x 3.28
- feet = millimeter x 0.00328
There are 2.54 centimeters in one inch. So you should perform the following equation to convert inch measurements to centimeters/meters/millimeters:
- centimeter = inch x 2.54
- meter = inch x 0.0254
- millimeter = inch x 25.4
There are 0.3937 inches to one centimeter. So you should perform the following equation to convert centimeters/meters/millimeters to inches:
- inch = centimeter x 0.3937
- inch = meter x 39.37
- inch = millimeter x 0.03937
There are 12 inches to one foot. So you should perform the following equation to convert feet to inches:
- inches = feet x 12
There are 0.0833 feet to one inch. So you should perform the following equation to convert inches to feet:
- feet = inches x 0.0833
| millimeter (mm) | centimeter (cm) | meter (m) | inch (in) | foot (ft) | |
| 1 millimeter (mm) | 1 | 0.1 | 0.001 | 0.03937 | 0.00328 |
| 1 centimeter (cm) | 10 | 1 | 0.01 | 0.3937 | 0.0328 |
| 1 meter (m) | 1000 | 100 | 1 | 39.37 | 3.28 |
| 1 inch (in) | 25.4 | 2.54 | 0.0254 | 1 | 0.0833 |
| 1 foot (ft) | 304.8 | 30.48 | 0.3048 | 12 | 1 |
The type of tape measure you use will depend on the object and the position of the object you want to measure. There are three main types of tape measure you can use:
- Self-retracting metallic tape measures
- Manually reeled tape measures
- Plastic tape measures
Plastic tape measures are used by tailors for measuring materials and human body lengths and widths, such as waist size and inner leg lengths. Metallic tape measures are good for measuring straight-edged objects such as tables or walls. A manually reeled tape measure can be useful for measuring longer objects that are not straight-edged, though you can also use a plastic tape measure for such measurements.
The end of a steel tape measure has a metallic component at the tip known as the 'hook.' When you want to take the measurement of anything with an edge, you can use the hook to clip onto the side of the object, which makes for a far more accurate measurement.
If you want to measure an inner nook of an area and you find the tape measure case is getting in your way, you should know that you can now buy tape measures that have a marked length on the case. You can even find ones with a transparent viewing window that allows you to see the very end of the tape measure within the case.
However, if you don't own one of these, you can still take an accurate measurement by bending the blade at the point it touches the object you are measuring. The steel is both sturdy and malleable, which allows you to bend the blade without causing any damage to it.
When using a metallic tape measure, it is important to never allow the blade to return at full speed when reeling it back in. While this may seem like the quick and easy option, it can be dangerous as the edge of the blade and the hook are sharp and can cause injury to your hand or to bystanders if returned to the case uncontrolled. Manufacturers recommend users wear protective goggles to prevent any damage to their eyes when using a metallic tape measure.
A measuring tape will either come with centimeter markings, inch markings, or both. These are then divided into millimeters or fractions of inches, with the half-inch mark usually in bold.
Measuring tapes are incredibly useful for moving house, fitting furniture, buying clothes, construction, and many other parts of our everyday lives. So it is vital that you know how to use them and which ones to use when they are needed.
