Prozentrechner – % von, Änderung & Rückrechnung
Kostenloser Prozentrechner: X % von Y, wie viel % A von B ist, Prozentzu-/abnahme und Rückrechnung — Sofortmathe, ohne Anmeldung.
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Berechnung lokal im Browser. Deutsche FAQ erscheinen unter dem Tool, wo verfügbar.
Prozentrechner
Prozentrechner
15% von 80
12
Verwandte Tools
Alle ToolsWhat Is a Percentage Calculator?
A percentage calculator solves everyday percent problems: how much is X% of a number, what percent one value is of another, and how much a value grew or shrank in percent terms. Use it for grades, tips, discounts, and growth rates.
Core Percent Formulas
X% of Y = Y × (X ÷ 100)
A is % of B = (A ÷ B) × 100
% change = ((New − Old) ÷ Old) × 100
Frequently Asked Questions
How do you calculate a percentage of a number?
Multiply by percent ÷ 100. Example: 15% of 80 = 12.
How do you calculate percentage increase?
((New − Old) ÷ Old) × 100. From 50 to 65 is a 30% increase.
What is a reverse percentage?
Finding the original before a % was applied — e.g. $80 after 20% off → $100 original.
Is this percentage calculator free?
Yes — free and private.