Percentage Calculator

Enter p as a percent (e.g., 15 = 15%). All fields sync live.

Mode 1 — How much is p% of x?

Example: 15% of 330 = 49.5. Relations: y = x × (p/100), p = 100 × y / x, x = 100 × y / p.

Mode 2 — x is what percent of y?

Formula: p = 100 × x / y (when y ≠ 0).

Mode 3 — x is p% of which number?

Example: 30 is 20% of 150. Formula: y = 100 × x / p (when p ≠ 0).

Actions

Step-by-step derivation

Mode 1
Provide any two of p, x, y.
Mode 2
Provide any two of x, y, p.
Mode 3
Provide any two of x, p, y.

Reference

  • y = x × (p/100), p = 100 × x / y, y = 100 × x / p
  • Here, user inputs p as a percentage number: 20 means 20%.
Notes: If y = 0, p = 100×x/y is undefined. If p = 0, y = 100×x/p is undefined.

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