X is what percent of Y?

This calculator answers one of the most common “real-life math” questions: “If I have X and the total is Y, what percent is X of Y?” You’ll see it in discounts, grading, budgeting, sales targets, workout tracking, nutrition labels, and anywhere you compare a part to a whole.

Percent literally means “per 100.” When you ask “X is what percent of Y,” you’re converting the fraction X / Y into a number out of 100. The result is (X ÷ Y) × 100.

If X equals Y, then X is 100% of Y. If X is half of Y, then X is 50% of Y. If X is bigger than Y, you’ll get a percent greater than 100% (that’s normal and often useful — for example, “we hit 120% of our goal”).

• Step 1 — Identify X: the part, amount, or observed value.
• Step 2 — Identify Y: the whole, total, baseline, or target.
• Step 3 — Divide: compute X ÷ Y to get a decimal ratio.
• Step 4 — Multiply by 100: convert the decimal ratio to percent.
• Step 5 — Choose rounding: use decimals for extra precision.

Money / budgeting

• Saved $250 out of $1,000: (250 ÷ 1000) × 100 = 25%.
• Spent $67 of a $200 budget: (67 ÷ 200) × 100 = 33.5%.

Grades / school

• 18 points out of 24: (18 ÷ 24) × 100 = 75%.
• 46 correct out of 50: (46 ÷ 50) × 100 = 92%.

Fitness / goals

• 7,500 steps out of 10,000: (7500 ÷ 10000) × 100 = 75%.
• 42 sales out of a 35 target: (42 ÷ 35) × 100 = 120% (over goal).

Click Calculate and the tool validates your inputs (especially that Y isn’t 0), runs the formula, and shows a readable sentence plus a simple visual meter. Everything runs locally in your browser.

• Swapping X and Y: X is the part; Y is the whole.
• Using the wrong whole: budgets use the budget as Y; grades use total points as Y.
• Dividing by zero: Y = 0 is undefined; pick a real total/baseline.
• Confusing with percent change: percent-of-total is not the same as change over time.

A percent can be over 100% when the part is larger than the whole. This is useful for: hitting a goal, exceeding quota, or spotting overspending (e.g., 112% of data used).

• 10%: Y ÷ 10
• 1%: Y ÷ 100
• 50%: half of Y
• 25%: half of half

• Is “X is what percent of Y” the same as “what percent is X of Y”?

  Yes. Both compute (X ÷ Y) × 100.

• How many decimals should I use?

  0–1 is great for everyday use; 2–4 helps for finance, science, or tighter comparisons.

• Does this store my data?

  Only if you click Save Result (stored locally on your device).

• How do I reverse it?

  If you know percent P and total Y: X = (P ÷ 100) × Y.

Educational tool only. Double-check important financial or health decisions with appropriate professionals.