Math

Calculate Percent Increase or Decrease

Built by Kevin Glover · @gloverbuilds · Verified formula

Find the percentage change between two values. See if the change is an increase or decrease and by how much.

📅 Updated April 2026 ✅ Formula verified 📖 4 min read 🆓 Free · No sign-up

In this article

The Percentage Change Formula
Percentage Change vs Percentage Points

La Formule

Variation % = ((Nouveau - Ancien) ÷ Ancien) × 100. De 50 € à 65 € : ((65-50)÷50)×100 = 30% d'augmentation. De 80 € à 60 € : -25%. Note : +50% puis -50% ne ramène PAS à l'original. 100 € +50% = 150 €. 150 € -50% = 75 €. Il faut +100% pour compenser -50%.

Applications

Investissements, augmentations de salaire, inflation, remises. Le changement en pourcentage est la façon la plus universelle d'exprimer des différences relatives.

⚡ CalcWolf Insight

Percentage change is one of the most commonly needed calculations in business, finance, and academics. "Percent increase calculator" and "percentage change calculator" combine for 100K+ monthly searches. Users include students, analysts, investors, and journalists verifying claims.

Frequently asked questions

Comment calculer ?▾

((Nouveau - Ancien) ÷ Ancien) × 100. De 200 à 250 : +25%. De 200 à 150 : -25%.

Pourquoi +50% et -50% ne s'annulent-ils pas ?▾

Parce qu'ils se calculent sur des bases différentes. 100 +50% = 150. 150 -50% = 75 (base 150, pas 100). Pour récupérer -50% : il faut +100%.

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Kevin Glover · @gloverbuilds

Founder, CalcWolf · GLVTS · Blickr

All formulas sourced from primary references — IRS publications, peer-reviewed research, and official standards. Results are tested against independent reference calculators before publishing. Rates and brackets updated when official sources change. Editorial policy →