A percentage calculator is an essential tool for swiftly computing various percentage-related calculations, such as determining what percentage one number is of another, calculating percentage increases or decreases, and finding the original number when a percentage of it is known. For instance, to find 20% of 50, multiply 50 by 0.20 to get 10. Conversely, to determine what percentage 10 is of 50, divide 10 by 50 and multiply by 100 to obtain 20%. These calculations are invaluable in everyday scenarios, including financial planning, data analysis, and academic assessments. Utilizing a percentage calculator ensures accuracy and efficiency in these computations.