Percentage

Calculate percent-of values, percent change, percent difference, and reverse percentages with visible formulas for discounts, markups, before-and-after values, and original-price reconstruction.

Calculate the percent increase from a start value to a final value, with the increase amount shown as the bridge between the two numbers.

Compare two measurements with symmetric percent difference, using the absolute gap divided by the average magnitude so neither value is treated as the original.

Calculate the final value after a percentage decrease by separating the original baseline, the amount removed, and the remaining value.

Back out the original value when you know the final value and the percentage increase or decrease that produced it.

Calculate the true sale price from a list price by applying the markdown first, then adding tax only to the discounted subtotal.

Compare a measured value with an accepted reference value by making absolute error visible first, then converting that error into a relative percentage.

Calculate tip, tax, service charges, and per-person shares for a shared restaurant bill.