# 2023 Step by step guide on how to calculate percent error

## Introduction percent error formula

Percent error is a common calculation in science and engineering. In its simplest form, percent error is defined as the difference between an observed or experimental value and a true or theoretical value, divided by the true or theoretical value and multiplied by 100. The formula for percent error is:

% Error = (observed value – theoretical value) / theoretical value * 100

For example, if you measure the length of an object to be 10 inches and the actual length is 9 inches, your percent error would be:

% Error = (10 inches – 9 inches) / 9 inches * 100 = 11.1%

There are many different sources of error in scientific measurements, so it’s important to know how to calculate percent error. This guide will show you how to calculate percent error step-by-step.

## What is percent error?

The percent error is the difference between the observed or measured value and the true or actual value of what is being measured. The formula for percent error is:

% Error = (Observed Value – True Value) / True Value x 100

For example, if you measure the length of an object to be 3 inches and the actual length is 2 inches, then your percent error would be:

% Error = (3 – 2) / 2 x 100 = 50%

## Why calculate percent error?

There are many reasons why you might want to calculate percent error. Maybe you did an experiment and want to know how accurate your results are, or maybe you need to know the margin of error for a survey you’re conducting. Whatever the reason, it’s easy to calculate percent error with a few simple steps. Here’s how:

First, take the absolute value of the difference between your measured value and the true value. This will give you the magnitude of the error without regard for whether it’s positive or negative.

Next, divide that number by the true value. This will give you the relative error.

Finally, multiply that number by 100 to get the percent error. And that’s it! Just three easy steps and you’ve got your percent error calculation.

## How to calculate percent error formula

Performing calculations is a critical part of many experiments and scientific investigations. In order to ensure that your calculations are accurate, it is important to understand how to calculate percent error. The percent error formula is used to calculate the percentage of error that occurs when an experimental value is compared to a theoretical value. This guide will show you how to calculate percent error step-by-step so that you can use this important tool in your own scientific investigations.

The first step in calculating percent error is to identify the experimental value and the theoretical value. The experimental value is the measured or observed value, while the theoretical value is the true or accepted value. In many cases, the experimental value will be given to you by your instructor or supervisor. However, if you are performing the experiment yourself, you will need to measure the desired quantity and record this as your experimental value.

Once you have identified the experimental and theoretical values, you are ready to calculate percent error using the following formula:

% Error = (Experimental Value – Theoretical Value) / Theoretical Value x 100

Let’s walk through an example calculation together. Suppose you are investigating the density of a material and you measure an experimental density of 1.5 g/cm3. The theoretical density of this material is known to be 2 g/cm3. Plugging these values into our percent error formula gives us:

% Error = (1.5 – 2) / 2 x 100

## Steps on how to calculate percent error formula

In order to calculate percent error, you will need to follow these steps:

First, take the experimental value and subtract it from the theoretical value.

Next, take that answer and divide it by the theoretical value.

Then, multiply that number by 100 in order to get percent.

And lastly, don’t forget to add the % sign! The final result should look like this: % error =

## Things to keep in mind when calculating percent error

1. The amount of error is calculated by taking the difference between the measured or observed value and the true or accepted value and then dividing this difference by the true or accepted value. The result is then multiplied by 100 to obtain percent error.

3. Another way to calculate percent error is to take the measured or observed value and divide it by the true or accepted value. The result is then multiplied by 100 to obtain percent error.

4. If you are measuring something with a known or accepted value, always use that as your starting point (0% error). For example, if you are measuring the length of a table with a ruler that has millimeter markings, and you measure to be 1.5 meters, your percent error would be ((actual length -measured length)/actual length)*100. In this case your actual length is 1 meter (1000 mm), so ((1-1.5)/1)*100 = -50%.

5. If you are measuring something and do not have a known or accepted value to compare your measurement to, your percenterror will be larger. This is due to the fact that when there is no definitive answer, there is more room for human error in interpretation of results.

6 Percenterror can also occur when using imperfect equipment . For example, if you are using an old pair of calipers that are not very precise, your results will have a greater margin of error than if you were using new equipment .