About PercentGuru
PercentGuru is a collection of percentage and finance calculators designed to give you accurate answers quickly. No accounts, no ads obscuring results, no slow page loads. You type a number, you get an answer.
What it covers
Two calculator hubs: percentage calculators for everyday maths (percentage increase, decrease, change, error, reverse percentage), and finance calculators for business and personal finance (profit margins, discounts, markup, ROI, loan repayments, break-even).
Why it exists
Most calculator sites are cluttered, slow, or buried under ads. PercentGuru is built to be the opposite: fast, focused, and useful. Each page explains the formula, shows worked examples, and answers the questions people actually ask — not just the obvious ones.
Accuracy
All calculations run in your browser using standard mathematical formulas. Results are for informational and educational purposes. For decisions involving significant money or legal obligations, verify with a qualified professional.