Percentage Calculator
Five percentage operations on one page. Type two numbers in any card below and the answer updates live, with the full working shown underneath. Values stay saved if you refresh.
What is X% of Y?
X is what percent of Y?
Percentage increase from X to Y
Percentage decrease from X to Y
Percentage difference between X and Y
Common Percentage Calculations
Quick lookup for the percentages people ask about most. Each row shows a fully worked answer — useful when you want to verify a mental shortcut or pull a single value without typing.
| Calculation | Result |
|---|---|
| 1% of 50 | 0.5 |
| 5% of 50 | 2.5 |
| 10% of 50 | 5 |
| 15% of 50 | 7.5 |
| 20% of 50 | 10 |
| 25% of 50 | 12.5 |
| 30% of 50 | 15 |
| 40% of 50 | 20 |
| 50% of 50 | 25 |
| 60% of 50 | 30 |
| 75% of 50 | 37.5 |
| 80% of 50 | 40 |
| 90% of 50 | 45 |
| 100% of 50 | 50 |
| 1% of 100 | 1 |
| 5% of 100 | 5 |
| 10% of 100 | 10 |
| 15% of 100 | 15 |
| 20% of 100 | 20 |
| 25% of 100 | 25 |
| 30% of 100 | 30 |
| 40% of 100 | 40 |
| 50% of 100 | 50 |
| 60% of 100 | 60 |
| 75% of 100 | 75 |
| 80% of 100 | 80 |
| 90% of 100 | 90 |
| 100% of 100 | 100 |
| Calculation | Result |
|---|---|
| 1% of 200 | 2 |
| 5% of 200 | 10 |
| 10% of 200 | 20 |
| 15% of 200 | 30 |
| 20% of 200 | 40 |
| 25% of 200 | 50 |
| 30% of 200 | 60 |
| 40% of 200 | 80 |
| 50% of 200 | 100 |
| 60% of 200 | 120 |
| 75% of 200 | 150 |
| 80% of 200 | 160 |
| 90% of 200 | 180 |
| 100% of 200 | 200 |
| 1% of 500 | 5 |
| 5% of 500 | 25 |
| 10% of 500 | 50 |
| 15% of 500 | 75 |
| 20% of 500 | 100 |
| 25% of 500 | 125 |
| 30% of 500 | 150 |
| 40% of 500 | 200 |
| 50% of 500 | 250 |
| 60% of 500 | 300 |
| 75% of 500 | 375 |
| 80% of 500 | 400 |
| 90% of 500 | 450 |
| 100% of 500 | 500 |
| Calculation | Result |
|---|---|
| 1% of 1000 | 10 |
| 5% of 1000 | 50 |
| 10% of 1000 | 100 |
| 15% of 1000 | 150 |
| 20% of 1000 | 200 |
| 25% of 1000 | 250 |
| 30% of 1000 | 300 |
| 40% of 1000 | 400 |
| 50% of 1000 | 500 |
| 60% of 1000 | 600 |
| 75% of 1000 | 750 |
| 80% of 1000 | 800 |
| 90% of 1000 | 900 |
| 100% of 1000 | 1000 |
| 1% of 10000 | 100 |
| 5% of 10000 | 500 |
| 10% of 10000 | 1000 |
| 15% of 10000 | 1500 |
| 20% of 10000 | 2000 |
| 25% of 10000 | 2500 |
| 30% of 10000 | 3000 |
| 40% of 10000 | 4000 |
| 50% of 10000 | 5000 |
| 60% of 10000 | 6000 |
| 75% of 10000 | 7500 |
| 80% of 10000 | 8000 |
| 90% of 10000 | 9000 |
| 100% of 10000 | 10000 |
How to Calculate Percentages
Three core formulas cover almost every percentage question. Keep them written down once and the rest is arithmetic.
1. Percent of a number
Worked example A
Find 18% of 250. Step 1: divide 18 by 100 → 0.18. Step 2: multiply by 250 → 45. So 18% of 250 is 45.
Worked example B (₹ context)
A shopkeeper in Pune offers a 12% discount on a ₹3,200 saree. Saving = (12 / 100) × 3200 = ₹384. Final price = 3200 − 384 = ₹2,816.
2. X is what percent of Y
Worked example A
A student scores 42 out of 60 in a test. Percent = (42 / 60) × 100 = 70%.
Worked example B (₹ context)
Your monthly EMI is ₹18,000 out of a take-home salary of ₹75,000. EMI as a share of salary = (18000 / 75000) × 100 = 24% — a quick check on whether the loan is within the usual 30–40% comfort band.
3. Percentage change
Worked example A
A company's revenue moves from $1.2M to $1.5M. Change = ((1.5 − 1.2) / 1.2) × 100 = 25% growth.
Worked example B (₹ context)
Your annual salary rises from ₹6,00,000 to ₹6,90,000. Hike = ((690000 − 600000) / 600000) × 100 = 15%. A negative result means a decrease.
Real-World Uses of Percentage Calculations
- Restaurant tips — quick 10%, 15% or 18% of the bill total.
- Shopping discounts — single sale percentages and stacked offers.
- Exam marks — converting raw scores into board or college percentages.
- GST and sales tax — 5%, 12%, 18% or 28% added on a base price.
- Interest rates — simple and compound interest on deposits or loans.
- Weight loss tracking — body weight change between two readings.
- Mark-up and margin — retailer cost vs selling price.
- Salary hikes — year-over-year and appraisal-cycle increments.
- Survey results — share of respondents picking each option.
Frequently Asked Questions
What is 20 percent of 100?
Answer: 20. Formula: (20 / 100) × 100 = 20.
With a base of 100, the percentage value always matches the result. That makes 100 the easiest base to work with. A 20% tip on a $100 bill is $20. A 20% mark on a 100-mark paper is 20 marks. Same logic scales: 5% = 5, 50% = 50, 75% = 75.
What is 30 percent of 100?
Answer: 30. Formula: (30 / 100) × 100 = 30.
Any percentage of 100 returns the same number — divide by 100, multiply by 100, the two operations cancel. A 30% discount on a ₹100 item saves ₹30, leaving ₹70. A 30% pass mark out of 100 means 30 correct. If the base is not 100, find 10% first, then multiply by 3.
What is 2 percent of 100?
Answer: 2. Formula: (2 / 100) × 100 = 2.
Starting point: 1% of 100 = 1. From there, 2% = 2, 3% = 3, and so on. Small percents like 2% come up in service charges, broker fees, and margins of error. To find 2% of any other number, multiply by 0.02 — so 2% of 5,000 = 100.
What is 10% of 60?
Answer: 6. Formula: (10 / 100) × 60 = 6.
Shortcut: 10% is the number with the decimal moved one place left. 60 becomes 6.0, which is 6. The same trick handles 600 → 60, 6,000 → 600, and 0.6 → 0.06. Once you have 10%, the rest is fast: 20% is double, 5% is half, 1% is two decimal places left.
What is 15 percent of 30?
Answer: 4.5. Formula: (15 / 100) × 30 = 4.5.
Mental method: 10% of 30 = 3, 5% of 30 = 1.5, sum = 4.5. The 10% + 5% pattern handles any 15% question without a calculator. A 15% tip on a $30 dinner is $4.50. A 15% sales tax on a ₹30 item adds ₹4.50, taking the total to ₹34.50.
What is 30 percent of 50?
Answer: 15. Formula: (30 / 100) × 50 = 15.
Mental split: 10% of 50 = 5; multiply by 3 to get 15. Alternative path: half of 30 is 15, and 50 is half of 100 — same answer. A 30% discount on a ₹50 lunch saves ₹15, leaving ₹35. Sanity check: 30% is just under one-third, and 50/3 ≈ 16.67, so 15 fits.
30 out of 40 as a percentage
Answer: 75%. Formula: (30 / 40) × 100 = 75.
Fraction in lowest form: 30/40 = 3/4. Decimal: 0.75. This is the classic three-quarter benchmark. Score 30 on a 40-mark test and you sit at a first-class threshold in most Indian boards. UK and US grading typically reads 75% as a strong B or A−. Quick check: 25% of 40 = 10, so 75% = 40 − 10 = 30.
10 out of 12 as a percentage
Answer: 83.33%. Formula: (10 / 12) × 100 = 83.333…
Fraction in lowest form: 10/12 = 5/6. Decimal: 0.8333. The recurring 3 comes from 1/6 = 0.1666… A 10/12 score sits firmly in the A range in most schools. Round to 83.33% for two decimal places, or 83.3% for one. Cross-check: 12 × 0.8333 ≈ 10.
10 out of 14 as a percentage
Answer: 71.43%. Formula: (10 / 14) × 100 = 71.4286…
Fraction in lowest form: 10/14 = 5/7. The decimal repeats because 7 never divides cleanly into powers of 10. Round to 71.43% for two decimals. A 10/14 score lands in the upper second-class band at most universities. Cross-check: 14 × 0.7143 ≈ 10.
10 out of 25 as a percentage
Answer: 40%. Formula: (10 / 25) × 100 = 40.
Fraction in lowest form: 10/25 = 2/5. Decimal: 0.4. Clean number, no rounding needed. A 10/25 score is below the pass mark in most Indian boards, where the cut-off is 33% or 35%. Quick shortcut: 25 × 4 = 100, so multiply any score out of 25 by 4 to get the percentage. 10 × 4 = 40.
10/15 as a percentage
Answer: 66.67%. Formula: (10 / 15) × 100 = 66.666…
Fraction in lowest form: 10/15 = 2/3. Decimal: 0.6667. The recurring 6 is the fingerprint of one-third — since 1/3 = 0.333…, two-thirds is 0.666… Two-thirds shows up in recipe ratios, traffic light timing, and exam pass cut-offs. Sanity check: 15 ÷ 3 = 5, and 5 × 2 = 10, confirming the fraction.
10/11 as a percentage
Answer: 90.91%. Formula: (10 / 11) × 100 = 90.9091…
Already in lowest form because 11 is prime. Decimal: 0.9091. The digits 09 repeat — that is the signature of every fraction with 11 in the denominator. A 10/11 score on a short quiz is solid A territory. Quick rule: 1/11 ≈ 9.09%, so 10/11 = 100% − 9.09% = 90.91%.
10/18 as a percentage
Answer: 55.56%. Formula: (10 / 18) × 100 = 55.555…
Fraction in lowest form: 10/18 = 5/9. Decimal: 0.5556. The 5 repeats forever, which is typical for any fraction over 9. Round to 55.56% for two decimals. A 10/18 score is a borderline pass on a short test. Cross-check: 5 ÷ 9 = 0.5555…, and × 100 = 55.55…%.
6/10 as a percent
Answer: 60%. Formula: (6 / 10) × 100 = 60.
Fraction in lowest form: 6/10 = 3/5. Decimal: 0.6. Anything divided by 10 converts instantly: move the digit one place and add the % sign. 6/10 = 60%, 7/10 = 70%, 9/10 = 90%. A 6/10 result is a typical second-class score in Indian boards and a passing C in most US schools.
30 out of 50 as a percentage
Answer: 60%. Formula: (30 / 50) × 100 = 60.
Fraction in lowest form: 30/50 = 3/5. Decimal: 0.6. Shortcut: 50 is half of 100, so double the numerator to read the percentage directly — 30 doubles to 60. Works for any /50 score: 25/50 = 50%, 40/50 = 80%, 45/50 = 90%. Standard for 50-mark unit tests and mock papers.
30/35 as a percentage
Answer: 85.71%. Formula: (30 / 35) × 100 = 85.7143…
Fraction in lowest form: 30/35 = 6/7. The digits 142857 repeat — the famous cyclic pattern of every seventh. Round to 85.71% for two decimals. A 30/35 score is a strong A grade on most quizzes. Cross-check: 5/35 = 1/7 ≈ 14.29%, so 30/35 = 100% − 14.29% = 85.71%.
45/100 simplified
Answer: 9/20. Method: divide top and bottom by their GCD, which is 5. 45 ÷ 5 = 9; 100 ÷ 5 = 20.
As a percent: 45%. As a decimal: 0.45. To verify the GCD, list shared factors of 45 (1, 3, 5, 9, 15, 45) and 100 (1, 2, 4, 5, 10, 20, 25, 50, 100). The largest is 5. After dividing, 9 and 20 share no factors — fully reduced.