Percentage Calculator: Free Online Instant Calculation
Author: Ian C. Langtree - Writer/Editor for Disabled World (DW)
Published: 2013/12/12 - Updated: 2024/07/03
Publication Type: Conversion, Calculation
Category Topic: Medical Calculators and Charts - Related Papers & Publications
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.
Defining Percentage
- Percentage
In mathematics, a percentage is a number or ratio expressed as a fraction of 100. The percentage is often denoted using the percent sign, %, or the abbreviation "pct." The word "percent" comes from "percent," which is short for "per centum," which means per hundred. In British English, the percent is sometimes written as two words "per cent" (although percentage and percentile are written as one word).
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 Content
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 is the founder and Editor-in-Chief of Disabled World, a leading resource for news and information on disability issues. With a global perspective shaped by years of travel and lived experience, Ian is a committed proponent of the Social Model of Disability-a transformative framework developed by disabled activists in the 1970s that emphasizes dismantling societal barriers rather than focusing solely on individual impairments. His work reflects a deep commitment to disability rights, accessibility, and social inclusion. To learn more about Ian's background, expertise, and accomplishments, visit his full biography.