Education Calculators
Percentage Calculator
Part / whole × 100.
How it works
Three steps, no friction.
- Step 1
Pick a mode
Percent of, part-of-whole, increase, or decrease.
- Step 2
Enter values
Two numbers — the tool validates them as you type.
- Step 3
Get the answer
Result, formula, and step-by-step explanation.
Benefits
Why teams choose WebRul.
- Fully client-side — your grades never leave the browser
- Add or remove rows freely; empty rows are ignored automatically
- Copy, download, or print Markdown / CSV / JSON / TXT reports
- WCAG 2.2 AA accessible with keyboard-first controls
FAQ
Questions, answered.
What is the formula for percentage?
Percentage = (part ÷ whole) × 100. For 'X% of Y', multiply Y by X ÷ 100.
How do I calculate percentage increase or decrease?
Percentage change = ((new − old) ÷ old) × 100. A positive result is an increase; a negative result is a decrease.
What happens if my 'whole' value is zero?
Percentages are undefined when the whole is zero (division by zero). The tool shows a warning instead of returning Infinity or NaN.
Is my data stored anywhere?
No. Every calculation runs entirely in your browser — nothing is uploaded, cached, or logged.
Can I download or print my result?
Yes. Every run produces Markdown, CSV, JSON, and plain-text artifacts you can copy, download, or print.
Related tools
Keep the flow going.
Need something custom?
Talk to the WebRul team about custom integrations, private tooling, or enterprise access.