How to read decimals on a tape measure

There are two types of scales commonly used on rulers; Fractional and Decimal. Fractional Rulers have graduations or marks based on fractions, for example 1/2", 1/4" 1/8", 1/16", etc.. Decimal Rulers have graduations or marks which are based on the decimal system such as 0.1, 0.01, etc.

Decimal Rulers can be based on any measuring system but are usually based on either the English measurement system inches (in) or the Metric measurement system of millimeters (mm), centimeters (cm) and meters (m).

We discuss here, Decimal Rulers based on the English measurement system of Inches.

Decimal Rulers utilizing inches normally have marks or graduations of 0.1" (1/10") and 0.01" (1/100)", some rulers may also have 0.020" (1/50") graduations.

In the drawing below, we show a ruler with graduations or marks of 0.1" (1/10") and 0.01" (1/100").
Often you will encounter rulers that do not have a legend which identifies what decimal of an inch is utilized on the scale. The ruler below has a legend of 100 which indicates that the smallest graduation or mark is 0.01" (1/100"). If a ruler has no legend the smallest graduation of an inch will have to be calculated. Simply count the number of spaces between graduations or marks contained within a single inch. If there are 10 the smallest graduation or mark is 1/10” or 0.1” as a decimal. If there are 100 the smallest graduation or mark is 1/100" or 0.01" as a decimal, etc.

CLICK HERE TO VIEW A WIDE VARIETY OF DECIMAL AND FRACTIONAL RULERS

‘Click here’ to view How To Read Decimal Rulers based on the Metric system

‘Click here’ to view How To Read Fractional Rulers based on the English (inch) system

A tape measure, sometimes also called a measuring tape, is a roll of metal tape with evenly graduated markings used for measuring. The tape is often yellow and rolled in a plastic case.

Tape measures are commonly used in construction, architecture, building, home projects, crafts, and woodworking. They usually come in lengths from 6 feet to 35 feet long.

Tape measures may have measurements in imperial and metric, imperial-only, or metric-only.

How to Read an Imperial Tape Measure

On an imperial tape measure, the markings represent lengths in inches and fractions of an inch.

Each large tick represents one inch (1″), and the ticks between represent the following fractions: 1⁄16“, 1⁄8“, 3⁄16“, 1⁄4“, 5⁄16“, 3⁄8“, 7⁄16“, 1⁄2“, 9⁄16“, 5⁄8“, 11⁄16“, 3⁄4“, 13⁄16“, 7⁄8“, and 15⁄16“.

To read a tape measure, find the number next to the large tick, and then find how many small ticks past it the measurement is. Add the number next to the large tick with the fraction to get the measurement. For instance, if your five ticks past the number 4 tick, then the measurement is 4 5⁄16“.

Reading a tape measure is just like reading a ruler.

What Do All the Markings Mean?

To read a measuring tape, you need to understand what all the markings mean. The large ticks are 1″ apart, and the small ticks are fractions of an inch. The numbers next to the large ticks indicate the distance from the end of the tape in inches.

The ticks in the middle of the inch markings are half-inch markings, and there is 1⁄2” between each inch marking and half-inch marking.

The ticks between the inch markings and half-inch markings are quarter-inch markings. There is 1⁄4” between the one-inch marking and the quarter-inch marking. There is 1⁄4” between each quarter-inch marking and the half-inch marking.

The second smallest ticks are eighth-inch markings, and there is 1⁄8” between the eighth-inch markings and the quarter-inch markings and one-inch markings.

The smallest ticks on a tape measure are sixteenth-inch markings. There is 1⁄16” between each marking on the tape measure.

Inch Fractions for Each Mark

See the decimal equivalents for all the fractions on a tape measure. You might also like our inch fraction calculator for converting between decimal and inch fractions and getting decimal equivalents.

Inch Fraction, Decimal and Millimeter Equivalents

How to Read a Metric Tape Measure

Metric tape measures have similar markings to imperial models, but the markings represent centimeters and millimeters. The larger markings on a metric tape with numbers are the centimeters and the smaller marks are millimeters.

Because there are 10 millimeters in a centimeter, there are 9 millimeter tick marks between each centimeter on the tape.

On a metric tape measure there is 1 cm between each large numbered tick mark and there is 1 mm between each smaller tick that is not numbered.

How to Use a Tape Measure

Get the most out of your measuring tape with the following tips for using them.

How to Use the Tape Lock

Almost all tape measures have a lock that will keep the tape measure from recoiling. This is useful if you need to take tension off of the tape measure or if you need to set the tape measure down while it is extended.

On this Stanley FatMax model, the slide lock is the large black button on the top. Sliding this down will lock the tape open to prevent recoil.

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How to Use the Sliding Hook

A signature feature of a tape measure is the hook on the end of the tape. This serves a dual purpose to prevent the tape from rolling into the case and allow hooking onto the end of items being measured.

You might notice that the end hook slides or moves just a bit. This is by design to account for the thickness of the hook, which allows the tape measure to be accurate when hooking onto a surface and also when butting the end up to a surface.

Be mindful of tape measures that do not have a sliding hook as they will not be as accurate.

How to Use the Framing Stud Hints

Most tape measures have red markings at certain intervals: 16″, 32″, 48″, 64″, and so on. These numbers are significant in that they indicate the middle of a stud on for 16″ on center framing.

Some tape measures also feature a black diamond symbol intervals that are 19.2″ apart. These diamonds are also used to indicate framing intervals for a wider stud or joist spacing.

How to Use the Nail Grab

The hook on a tape measure often has a small hole or groove in it. This is actually used to allow hooking the hook on a nail or screw, so it doesn’t slide off when making long measurements.

This is especially useful for longer measurements, such as measuring across the length of a room or patio.

On the hook above, the oval cutout is used to hook onto a nail or screw.

Use the Sides of the Hook

Some tape measures, especially framing tapes, have large hooks that can be used to grip surfaces on the side of the hook. Using these can improve the hook’s gripping ability and improve the accuracy of measurements since the tape measure will not need to be twisted to read the markings.

How to Choose the Right Tape Measure

There are many tape measures on the market, and many serve very different purposes. When choosing the one that’s right for you, consider what you’ll be using it for, how long you need it to be, and how much you’d prefer to spend.

When choosing a tape measure, consider the following features to find a tape measure that’s right for you and your needs.

• Size and ease of reading the markings
• Imperial or metric markings
• Length of the tape
• Physical size of the tape
• Standout length for measuring longer lengths
• Locking features
• Durability
• Price

See our review of the best tape measures to find which tape measure we found to be the best and for reviews on several leading tape measures on the market. In a pinch, you can even print a tape measure to save a trip to the store.

How do I read a tape measure?

Do you start at 1 or 0 on a tape measure?