Skip to main content
Percentage Calculator
Calculate

What Percent Is X of Y?

Turn a score, a share or a portion into a percentage. Enter the part and the total it belongs to — this is the calculation behind exam results, completion rates and market share.

X is what percent of Y?

Enter your numbers and press Calculate — the full working appears here.

The formula

Dividing the part by the whole gives a decimal share of one. Multiplying by 100 restates that share per hundred, which is all a percentage is.

(Part ÷ Whole) × 100

(25 ÷ 200) × 100 = 12.5%

A quick sanity check: if the part is less than half the whole, your answer must be under 50%.

Worked examples

You scored 437 marks out of a possible 500. What is your percentage?

  1. Divide your marks by the total available.437 ÷ 500 = 0.874
  2. Multiply by 100.0.874 × 100 = 87.4%

Answer87.4%

Open this example in the calculator →

Your team closed 18 of the 240 deals in the pipeline. What share is that?

  1. Divide the closed deals by the total.18 ÷ 240 = 0.075
  2. Multiply by 100.0.075 × 100 = 7.5%

Answer7.5%

Open this example in the calculator →

Common uses

  • Exam and test scores — converting marks out of any total into a percentage that can be compared across subjects.
  • Attendance — days present out of days in the term.
  • Completion and progress — tasks finished out of tasks planned.
  • Market and vote share — one participant's count out of the total.
  • Conversion rates — purchases out of visits, or replies out of messages sent.
  • Nutrition and composition — grams of one ingredient out of total weight.

Working in the opposite direction — you know the percentage and want the total — is handled by the X is Y% of what number calculator.

Frequently asked questions

How do I find what percent one number is of another?
Divide the part by the whole, then multiply by 100. For 25 out of 200: 25 ÷ 200 = 0.125, and 0.125 × 100 = 12.5%.
25 is what percent of 200?
12.5%. Twenty-five is one eighth of two hundred, and one eighth expressed per hundred is 12.5.
How do I calculate my exam percentage?
Divide the marks you scored by the total marks available, then multiply by 100. Scoring 437 out of 500 gives 437 ÷ 500 × 100 = 87.4%. For several papers, add all your marks together and divide by the combined total rather than averaging the individual percentages — papers with different totals do not carry equal weight.
Which number goes on top?
The part — the smaller quantity you are describing — goes on top, and the whole it belongs to goes underneath. If your answer comes out above 100%, you have either swapped them or the part genuinely exceeds the whole.
What if the total is zero?
There is no answer. Nothing can be a percentage of zero, because that would mean dividing by zero. The calculator explains this rather than returning an error code.

Related calculators