CalKit

Percentage Calculator

Calculate percentages, discounts, and rate of change.

200의 15%
30

Overview

The Percentage Calculator handles all percentage-related computations including basic percentages, discounts, percentage change, and ratio conversions. It is useful for everyday shopping discounts, data analysis, and business calculations.

Formula

Percentage = (Part / Whole) × 100

Discount Price = Original Price × (1 - Discount Rate / 100)

Percentage Change (%) = ((New Value - Old Value) / Old Value) × 100

A% of B = B × (A / 100)

How to Use

  1. 1Select the calculation type (basic percentage, discount, percentage change, etc.).
  2. 2Enter the base value (whole value).
  3. 3Enter the percentage or comparison value.
  4. 4The result is calculated and displayed automatically.

Tips

  • ✔Quickly check 'what percentage of the original price' when shopping for discounts.
  • ✔When calculating percentage change, be careful not to confuse the base (old) and comparison (new) values.
  • ✔Percentage points (%p) and percentages (%) are different concepts. Going from 5% to 10% is a 100% increase, but only a 5%p difference.

FAQ

Q. What is the difference between percent (%) and percentage points (%p)?

Percent (%) is a ratio relative to a base value, while percentage points (%p) represent the simple arithmetic difference between two percentage values. For example, if an interest rate rises from 3% to 5%, it increases by 2%p, but the rate of increase is about 66.7%.

Q. Are discount rate and margin rate the same thing?

No. The discount rate is the ratio of the discount amount to the original price, while the margin rate is the ratio of profit to the selling price. Since the base values differ, the percentages differ even for the same monetary amounts.

Q. What is the most common mistake in percentage calculations?

Setting the wrong base value. In 'What percent of B is A?', the base is B. In 'increase from A to B', the base is A. Swapping the base completely changes the result.

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