Solve percentage increases, decreases, fractions, and discounts.
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. Zero egress.
Zero network latency. Operates completely offline with zero dependencies on third-party backend servers or cloud services.
Built according to official RFC specifications, cryptographic test vectors, and enterprise-grade data transformation standards.
Select 'What is X% of Y', 'X is what % of Y', or 'Percentage Increase/Decrease'.
Enter your numbers into the calculation fields.
See calculated percentage values, difference amounts, and step-by-step arithmetic.
Subtract the original value from the new value, divide by the original value, and multiply by 100.
Yes, calculations use double-precision floating-point arithmetic with precise decimal formatting.
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