Percentage Calculator – Calculate Percentage Online (Free Tool)

Percentage Calculator covers the three percentage operations that come up daily: "what is X% of Y", "X is what percent of Y", and "% change from X to Y". Each mode has clearly labelled fields so you don't have to think about which formula applies — pick the question you're asking and the answer appears.

• Works offline after the first page load
• Lightweight page weight that loads quickly even on slow connections
• Works on desktop, tablet, and mobile in any modern browser
• No upsell to a paid plan: every feature is free forever
• Designed for everyday quick tasks — open the page, get the answer, move on

1. Pick a mode: "X% of Y", "X is what % of Y", or "% change from X to Y"
2. Enter the two numbers — the result updates instantly
3. Copy the result or use it as the input for another calculation

• Tax, tip, and discount math at the checkout
• Test scores and grading conversions
• Sales growth, revenue change, and KPI deltas
• Quick stats for reports without firing up a spreadsheet

% change shows a huge number when starting from a small base.

Small denominators amplify percentage changes (e.g. 1 → 10 is +900%). Mathematically correct — interpret with care when base values are small.