GDP Deflator Formula Calculator GDP deflator. Nominal GDP ($) Real GDP ($) GDP deflator 125 Step-by-step with your numbers: 1. Values used: 2. Nominal GDP = 25,000 $ 3. Real GDP = 20,000 $ 4. GDP deflator = 125 Did we solve your problem today? 👍 Yes 👎 No Thanks for the feedback! Deflator = nominal/real × 100. FAQ Inflation? Changes in the deflator measure GDP inflation. Related calculators Real GDP Calculator Convert nominal GDP to real GDP using the deflator. GDP Calculator Find GDP using the expenditure approach. Inflation Rate Calculator Find the inflation rate from two CPI values.