Percentage Calculator
Three percentage calculators in one: find X% of a number, find what percentage one number is of another, or calculate the percentage increase or decrease between two values.
Percentage Calculator
Percentage (%)18% of 1,000 =
180
How It Works
Percentages (from Latin 'per centum' — per hundred) express a number as a fraction of 100. They appear in everyday life: GST and tax rates, discounts, interest rates, exam scores, and statistical data. There are three core percentage problems: (1) Finding a percentage of a value — used for calculating tax amounts, discounts, tips; (2) Expressing one number as a percentage of another — used for test scores, market share, completion rates; (3) Percentage change — used to measure growth, inflation, price changes. The key distinction: a 50% increase followed by a 50% decrease does NOT return to the original value (100 → 150 → 75), because percentage change is always relative to the current base.
Formula
X% of Y = (X/100) × Y. X as % of Y = (X/Y) × 100. % change = ((New − Old) / |Old|) × 100.
Frequently Asked Questions
What is percentage and how is it calculated?
A percentage expresses a number as a fraction of 100. 'X percent of Y' means X parts out of every 100 parts of Y. To calculate X% of Y: multiply Y by X and divide by 100. For example, 18% of ₹5,000 = (18/100) × 5,000 = ₹900.
What is the percentage change formula?
Percentage change = ((New Value − Old Value) / |Old Value|) × 100. If the result is positive, it's an increase; if negative, it's a decrease. Example: price rises from ₹200 to ₹250 → change = ((250−200)/200) × 100 = 25% increase. Always divide by the original (old) value, not the new one.
What is the difference between percentage points and percent?
Percentage points measure the arithmetic difference between two percentages. Percent (%) measures relative change. Example: interest rate rises from 6% to 8% — that's a 2 percentage point increase, but a 33.3% relative increase (2/6 × 100). The distinction matters in finance and policy — 'interest rates rose 2%' (relative) is very different from 'rose by 2 percentage points' (absolute).
How do I work backwards from a total with percentage?
To find the original value before a percentage was added (e.g., GST-inclusive price): Original = Total ÷ (1 + rate/100). Example: price including 18% GST is ₹1,180 → original = 1180 ÷ 1.18 = ₹1,000. Similarly, to find the original before a discount: if ₹750 is after 25% off, original = 750 ÷ (1 − 0.25) = ₹1,000.
What is a percentage vs a percentile?
A percentage is a ratio out of 100. A percentile is a rank that tells you what percentage of a distribution falls below a given value. Scoring 90% on an exam means you got 90 out of 100 marks. Being in the 90th percentile means you scored better than 90% of test takers — your actual score depends on the distribution.
How are percentages used in finance?
Interest rates (FD, loan EMI, repo rate) are expressed as percentages per annum. GST rates (5%, 12%, 18%, 28%) are percentages applied to base price. Investment returns are percentage gains/losses on initial capital. Inflation is the percentage increase in price level. Discount rates are percentage reductions from MRP. Income tax slabs are percentage rates applied to taxable income within each slab.