Percentage Calculator: Free Online Instant Calculation

Ian C. Langtree - Writer/Editor for Disabled World (DW)
Published: 2013/12/12 - Updated: 2024/07/03
Publication Type: Conversion, Calculation
Topic: Medical Calculators and Charts - Publications List

Page Content: Synopsis - Introduction - Main

Synopsis: Free online instant calculator for finding a percentage of a number as well as reverse percentage calculations. The percent value is computed by multiplying the numeric value of the ratio by 100.

Introduction

The percent value is computed by multiplying the numeric value of the ratio by 100. For example, to find 50 apples as a percentage of 1250 apples, first, compute the ratio 50/1250 = 0.04, then multiply by 100 to obtain 4%. The percent value can also be found by multiplying first, so in this example, the 50 would be multiplied by 100 to give 5,000, and this result would be divided by 1250 to give 4%.

Main Item

To calculate a percentage of a percentage, convert both percentages to fractions of 100 or decimals and multiply them. For example, 50% of 40% is calculated; (50/100) x (40/100) = 0.50 x 0.40 = 0.20 = 20/100 = 20%.

NOTE: It is incorrect to divide by 100 and use the percent sign simultaneously. E.g. 25% = 25/100 = 0.25, not 25% / 100, which actually is (25/100) / 100 = 0.0025. A term such as (100/100)% would also be incorrect; this would be read as 1 percent even if the intent was to say 100%. Other Examples:

• 1 percent (1%) = 1 part per 100 = 1/100 = 0.01 (a portion less than a whole)
• 100 percent (100%) = 100 parts per 100 = 100/100 = 1 (a portion equal to a whole)
• 110 percent (110%) = 110 parts per 100 = 110/100 = 1.1 (a portion greater than a whole)

Author Credentials: Ian was born and grew up in Australia. Since then, he has traveled and lived in numerous locations and currently resides in Montreal, Canada. Ian is the founder, a writer, and editor in chief for Disabled World. Ian believes in the Social Model of Disability, a belief developed by disabled people in the 1970s. The social model changes the focus away from people's impairments and towards removing barriers that disabled people face daily. To learn more about Ian's background, expertise, and achievements, check out his bio.