toololis
Voltar Voltar to Finance
%

Calculadora de Porcentagem — Ferramenta online grátis

Calcule porcentagens, aumentos, descontos e mais

Calculadora de porcentagem grátis. Descubra X% de Y, aumento/desconto percentual e muito mais. Instantâneo e no navegador.

%

Enter numbers to calculate

📚
Saiba mais

Free percentage calculator — four calculations in one

Ferramentaolis Percentage Calculadora handles the four most common percentage questions in one place: X% of Y, X is what percentage of Y, percentage change from A to B, and adding/subtracting a percentage to a value. Live results as you type. Works on phones, tablets, and desktop.

The four percentage questions

  • X% of Y — "What is 20% of 80?" → 16 (for tips, discounts, tax)
  • X is what % of Y — "30 is what % of 150?" → 20% (for test scores, market share)
  • % Change — "From 50 to 75?" → +50% (for price changes, performance)
  • Add / Subtract % — "100 plus 15%?" → 115 (for tax, markup, discount)

How to use this tool

  1. 1

    Choose a calculation type

    Four tabs handle the four common percentage questions: X% of Y, X is what % of Y, percentage change, and after-percentage value.

  2. 2

    Enter your numbers

    Type into the two number fields. Results update live as you type — no need to click a button.

  3. 3

    Read the result

    The big number at the bottom is your answer. A plain-language sentence explains what it means.

Common real-life percentage calculations

  • Restaurant tip — Bill $80, 18% tip: 80 × 0.18 = $14.40
  • Sale discount — $120 item, 25% off: 120 × 0.75 = $90
  • Sales tax — $50 + 8% tax: 50 × 1.08 = $54
  • Test score — Got 42/50: (42/50) × 100 = 84%
  • Stock gain — Bought $100, now $143: (143-100)/100 × 100 = 43% gain
  • Salary raise — $50k + 8% raise: 50000 × 1.08 = $54,000

Frequently Asked Questions

How do I calculate X% of Y?
Multiply Y by X, then divide by 100. Example: 20% of 80 = (80 × 20) / 100 = 16. Use the first tab to do this automatically.
How do I find what percentage X is of Y?
Divide X by Y, then multiply by 100. Example: 30 is what % of 150? (30 / 150) × 100 = 20%. Use the second tab.
How do I calculate percentage change?
Subtract the old value from the new, divide by the old value, multiply by 100. Example: going from 50 to 75 is a (75-50)/50 × 100 = 50% increase. Negative results mean a decrease. Use the third tab.
How do I add X% to a value?
Multiply the value by (1 + X/100). Example: 100 plus 15% tax = 100 × 1.15 = 115. Tab four does this; negative percentages subtract.
Why does percentage math seem confusing?
People mix up "percentage of" with "percentage change". A 50% increase followed by a 50% decrease does NOT return to the original — you end up at 75% of the start. Always clarify which question you're asking.
Is this calculator accurate for financial use?
Yes, for standard percentage math. For complex finance (compound interest, tax brackets, discount stacking), use a purpose-built tool like a mortgage or tax calculator.

Pontos-chave

  • Percentage Calculadora is a free, browser-based finance tool — calculate percentages, increases, decreases & more.
  • Não signup, no downloads, no file uploads — your data stays on your device.
  • Works on desktop, tablet, and mobile. Install as a PWA for offline access.

How to Use Percentage Calculadora

  1. Open the tool: Launch Percentage Calculadora on Ferramentaolis — no account or download needed.
  2. Enter your data: Paste text, enter values, or select a file directly in your browser.
  3. Get instant results: Everything is processed locally — results appear immediately.
  4. Copy or download: Save your output or share it. Bookmark for quick access next time.

Percentage Calculadora — Quick Facts

Preço
Grátis — sem limites, sem marca d’água, sem paywall
Privacidade
100% no navegador — nenhum dado é enviado a servidores
Plataforma
Qualquer navegador moderno — desktop, tablet ou celular
Categoria
Finance Ferramentas on Ferramentaolis
Offline
Works offline after first visit (Progressive Web App)
RecursoDetalhes
FerramentaPercentage Calculadora
CategoriaFinance
Cadastro necessárioNão
Upload de arquivoNenhum — processado no navegador
Suporte mobileTotalmente responsivo
CustoGrátis para sempre

Why Use Percentage Calculadora?

You should try Percentage Calculadora for a quick, private way to calculate percentages, increases, decreases & more. All processing happens in your browser. Your files and data never leave your device. According to web.dev, client-side processing is the gold standard for privacy.

On the other hand, dedicated APIs or desktop tools suit batch processing better. They also handle server-side automation. For everyday tasks, browser tools offer the best speed, privacy, and convenience.

You might also like

🔒
100% Privacidade. Esta ferramenta funciona inteiramente no seu navegador. Seus dados nunca são enviados a nenhum servidor.