How To Calculator Percent Error

Percent Error Formula:

\[ \% Error = \frac{|Measured - Actual|}{Actual} \times 100 \]

Percent Error:

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is Percent Error?

Percent error is a measure of how inaccurate a measurement is, standardized to how large the measurement is. It is the absolute value of the error divided by the actual value, multiplied by 100%.

2. How Does the Calculator Work?

The calculator uses the percent error formula:

\[ \% Error = \frac{|Measured - Actual|}{Actual} \times 100 \]

Where:

\( Measured \) — The experimental or observed value
\( Actual \) — The true or accepted value
\( |Measured - Actual| \) — Absolute value of the difference

Explanation: The formula calculates the relative error as a percentage, providing a standardized way to compare measurement accuracy across different scales.

3. Importance of Percent Error Calculation

Details: Percent error is crucial in scientific experiments, quality control, and data analysis to quantify the accuracy of measurements and identify potential sources of error.

4. Using the Calculator

Tips: Enter both measured and actual values. The actual value cannot be zero. The calculator will compute the absolute difference and express it as a percentage of the actual value.

5. Frequently Asked Questions (FAQ)

Q1: What is considered a good percent error?
A: This depends on the field. In most scientific experiments, less than 5% is considered acceptable, while in engineering, requirements may be stricter.

Q2: Can percent error be negative?
A: No, percent error is always positive because it uses the absolute value of the difference between measured and actual values.

Q3: What if the actual value is zero?
A: Percent error is undefined when the actual value is zero, as division by zero is mathematically impossible.

Q4: How is percent error different from percent difference?
A: Percent error compares a measured value to an accepted value, while percent difference compares two experimental values without assuming one is correct.

Q5: When should I use percent error?
A: Use percent error when you have a known "true" value to compare against, such as in calibration, quality assurance, or when verifying experimental results against established standards.