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What Percent Is X of Y? Calculator

Type the part and the whole to see what percentage the part is, for test scores, budgets, survey answers or anything out of a total.

is what percent of ?

Percentage of the whole

75%

42 is 75% of 56.

42 (the part)75%
56 (the whole)100%

How to work out what percent one number is of another

Divide the part by the whole, then multiply by 100. For 42 out of 56: 42 ÷ 56 = 0.75, and 0.75 × 100 = 75%. The division gives the share as a decimal; multiplying by 100 says the same share per hundred.

Some shares never come out even. One out of three is 0.333… with the 3 repeating for ever, so it is 33⅓% exactly, or 33.33% to two decimal places. This calculator divides with exact fractions and only rounds what it shows, so you can add decimal places from the ⋯ menu without the answer drifting.

The whole must be the thing you are measuring against. “What percent of the class passed?” divides by the class size; “passes as a percent of fails” divides by the number who failed, which is a different question with a different answer.

percentage = part ÷ whole × 100

  • A percentage is a ratio expressed as a fraction of 100, so 75% and 3/4 and 0.75 are the same number written three ways. Source: Wikipedia, Percentage.

Test scores as percentages

Marks out of 20, 25, 40 and 50, as percentages to one decimal place.

Marks out of 20, 25, 40 and 50, as percentages to one decimal place.
ScoreOut of 20Out of 25Out of 40Out of 50
15%4%2.5%2%
210%8%5%4%
315%12%7.5%6%
420%16%10%8%
525%20%12.5%10%
630%24%15%12%
735%28%17.5%14%
840%32%20%16%
945%36%22.5%18%
1050%40%25%20%
Show all 20 rows
1155%44%27.5%22%
1260%48%30%24%
1365%52%32.5%26%
1470%56%35%28%
1575%60%37.5%30%
1680%64%40%32%
1785%68%42.5%34%
1890%72%45%36%
1995%76%47.5%38%
20100%80%50%40%

Frequently Asked Questions

What percent is 18 out of 24?

18 ÷ 24 = 0.75, so it is 75%. Both numbers share a factor of 6, which is why the fraction simplifies to 3/4.

How do I find what percent a number is of a total when the part is bigger?

The same way: 30 out of 20 is 30 ÷ 20 × 100 = 150%. A result over 100% just means the part is larger than the whole you compared it with.

Why does 2 out of 3 show as 66.67%?

2 ÷ 3 = 0.6666… with the 6 repeating, so the exact answer is 66⅔%. Rounded to two decimal places the last 6 rounds up, giving 66.67%.