The Percentage Increase Calculator is a free online tool that instantly computes percentage changes between two values. It supports both increases and decreases, displaying negative results in red. Users can enter any two of three fields (original value, new value, percentage change) and the third auto-calculates."Fill any two — the third auto-calculates."Key features include a Value + Percent mode for quick calculations, step-by-step formula display, and plain English results. It is ideal for salary raises, price increases, stock growth, and property value changes.FeatureDescriptionAuto-calculationResults update as you typeThree-field inputSolve for any missing valueDecrease supportNegative percentages shown in red