Calculate Percentage Increase Between Two Numbers
Find the percentage increase from one value to another. Simple formula with step-by-step explanation.
The Percentage Increase Formula
% Increase = ((New - Original) / Original) × 100. From 200 to 250: (250-200)/200 × 100 = 25% increase. If the new value is smaller, the result is negative — a decrease. This formula works for any values: prices, populations, test scores, revenue, or any measurable quantity you want to compare over time.
Common Mistakes
The most common error: confusing which number goes in the denominator. The original (starting) value is always the denominator. Going from 80 to 100 is a 25% increase (20/80). Going from 100 to 80 is a 20% decrease (20/100). The percentages differ because the base is different. Also remember: a 50% increase followed by a 50% decrease does NOT return to the original — $100 → $150 → $75.
Percent increase calculator captures a different search intent than percentage change — users specifically want to know "how much did X go up by." This variant alone gets 60K+ monthly searches and is often the exact query students type for homework.
