Inflation Calculator Formula

Understand the math behind the inflation calculator. Each variable explained with a worked example.

Formulas Used

Future Cost

future_cost = current_amount * pow(1 + inflation_rate / 100, years)

Purchasing Power of Current $

purchasing_power = current_amount / pow(1 + inflation_rate / 100, years)

Cumulative Inflation

total_inflation = (pow(1 + inflation_rate / 100, years) - 1) * 100

Variables

VariableDescriptionDefault
current_amountCurrent Amount(USD)100
inflation_rateAnnual Inflation Rate(%)3
yearsNumber of Years(years)10

How It Works

Inflation Formula

Future Cost = Current Amount × (1 + r)^n

Where r = annual inflation rate and n = number of years. Inflation erodes purchasing power over time.

Worked Example

$100 with 3% annual inflation over 10 years.

current_amount = 100inflation_rate = 3years = 10
  1. 01Future cost = $100 × (1.03)^10
  2. 02= $100 × 1.3439 = $134.39
  3. 03Today's $100 will only buy $74.41 worth of goods in 10 years
  4. 04Cumulative inflation = 34.4%

Frequently Asked Questions

What is the average inflation rate?

The US long-term average is about 3% per year. Recent years have seen higher inflation (6-9% in 2022).

Learn More

Guide

Inflation Impact on Savings

Understand how inflation erodes your savings and purchasing power over time. Learn strategies to protect your money, calculate real returns, and invest to outpace inflation.

Ready to run the numbers?

Open Inflation Calculator