Free Index Number Calculator
Calculate a simple price or quantity index number relative to a base period value.
Index Number
125.0000
Change from Base (%)25.0000
Current / Base Ratio1.250000
Index Number vs Current Period Value
How to Calculate an Index Number
Formula
Index = (Current Value / Base Value) * Base Index
An index number expresses a value relative to a base period. The base period is typically set to 100. An index of 125 means a 25% increase from the base. Index numbers are used for price indices (CPI), stock indices, and economic indicators.
Example Calculation
A commodity priced at $125 today vs. $100 in the base year.
- 01Index = (125 / 100) * 100 = 125
- 02Change from base = ((125/100) - 1) * 100 = 25%
- 03The price is 25% above the base period.
Frequently Asked Questions
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