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Word Usage: Percent or Percentage?

The words percent and percentage are closely related—does it matter how they are used in a sentence? Read this word usage tip to find out.

The rule for using percent and percentage is straightforward. The word percent (or the symbol %) accompanies a specific number, whereas the more general word percentage is used without a number.


percent (adverb, noun): of each hundred

Fifteen percent of the control group responded to treatment with Drug A.

More than 95% of the participants who responded to the survey reported positive results.

percentage (noun): part of a whole that can be expressed in hundredths

A large percentage of the population has been exposed to rotavirus.

The percentage of the population exposed to rotavirus is between 70% and 75%.

Quick Tips: Percent vs Percentage

Speedy pencil: quick grammar tips
  1. Always write out the number and the word percent at the beginning of a sentence (eg, "Ten percent...").
  2. The noun percentage requires an adjective to describe its size (eg, "a large percentage") when it does not refer to specific numbers in the sentence.
  3. Some style guides recommend a numeral and the symbol % rather than the word percent, even if the number is less than 10 (eg, "A total of 5%...").


Iverson C, Christiansen S, Flanagin A, et al. AMA Manual of Style: A Guide for Authors and Editors. 10th ed. New York, NY: Oxford University Press; 2007.

Merriam-Webster's Collegiate Dictionary. 11th ed. Springfield, MA: Merriam-Webster, Inc.; 2007.

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