Percentages & Ratio ⚖️

Work out percentage change, find the original price before a discount, share an amount in a ratio, simplify ratios and compare packs for the best buy — every answer with its working.

Multipliers Reverse % Best buy Nothing leaves your device

Percentage change from A to B

fromto
Result

    Increase or decrease by a percentage

    ±%
    Result

      Good to know

      Use the multiplier

      A 12% increase is × 1.12 and a 12% decrease is × 0.88. One multiplication does the job, and it works backwards too: divide by the multiplier to find the original.

      Ratios are parts, not amounts

      3 : 5 means 8 equal parts. Find what one part is worth first, then multiply — and check the shares add back to the total.

      Nothing leaves your device

      Everything is worked out in your browser and nothing is saved. The address bar keeps the numbers, so a link opens the same working.

      Mr. Nat Bunchhai Tool created by
      លោក ណាត ប៊ុនឆ័យ · Mr. Nat Bunchhai

      Tel 096 653 21 03 · FB: Bunchhai Nat
      natbunchhai.17@gmail.com


      Alpha Academy Cambodia

      Percentages are everywhere in real life.

      Our tutors make percentages and ratio practical — prices, discounts, recipes and maps — for primary and secondary students.