GDP Deflator Calculator — Nominal vs Real GDP Price Index
Compute the GDP deflator — the broadest measure of economy-wide price changes — from nominal GDP (current prices) and real GDP (constant prices). Optionally compare two deflator readings to find the inflation rate between periods.
(Nominal GDP ÷ Real GDP) × 100 — price index relative to the base year
- 1
Nominal ÷ Real GDP
25,000 ÷ 22,000 = 1.136364 - 2
GDP Deflator
1.136364 × 100 = 113.64A deflator of 100 equals the base-year price level; above 100 means prices have risen.
How does this calculator work?
GDP Deflator = (Nominal GDP ÷ Real GDP) × 100. It measures economy-wide price change relative to a base year (deflator = 100 at the base). Unlike the CPI, it covers all domestic output, not just a consumer basket. A deflator of 114 means prices are 14% above the base year.
Formula
How this is calculated
The GDP deflator (also called the implicit price deflator) measures the ratio of nominal GDP to real GDP, multiplied by 100. Nominal GDP values output at current market prices; real GDP re-values the same output at a fixed base-year price level. Their ratio isolates the pure price change: a deflator of 114 means prices are 14% higher than in the base year, when the deflator equalled 100.
Unlike the Consumer Price Index (CPI), which tracks a fixed basket of consumer goods, the GDP deflator covers the entire economy — consumption, investment, government spending, and net exports — and automatically adjusts its basket each period to reflect actual output. This makes it a broader but slightly different measure of inflation.
If you have deflator readings for two different periods, the inflation rate between them is ((D₂ − D₁) / D₁) × 100. Entering both optional fields activates this calculation. Note that national statistical agencies compute official deflators with chain-weighted methods that differ from a simple ratio; this calculator uses the straightforward formula and is intended for educational and illustrative purposes.
Frequently asked questions
CPI tracks a fixed basket of consumer goods and services bought by households. The GDP deflator covers all domestically produced goods and services (including investment and government) and uses a changing, economy-wide basket. GDP deflator excludes imports; CPI includes imported consumer goods. Both measure inflation but can give different readings.
A deflator above 100 means the current price level is higher than the base-year price level — there has been net inflation since the base year. For example, a deflator of 120 means prices are 20% higher than in the base year. A deflator below 100 would indicate deflation (falling prices) relative to the base year.
Real GDP = (Nominal GDP ÷ GDP Deflator) × 100. For example, if nominal GDP is $25 trillion and the deflator is 125, real GDP = ($25T ÷ 125) × 100 = $20T. The conversion removes price changes so you can compare output volumes across years.
Also known as
TG we-Calculate Editorial Team. (2026). GDP Deflator Calculator — Nominal vs Real GDP Price Index [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/gdp-deflator-calculator
TG we-Calculate Editorial Team. "GDP Deflator Calculator — Nominal vs Real GDP Price Index." TG we-Calculate. 2026. https://we-calculate.com/calculator/gdp-deflator-calculator.
TG we-Calculate Editorial Team, "GDP Deflator Calculator — Nominal vs Real GDP Price Index," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/gdp-deflator-calculator
@misc{wecalculate_gdp_deflator_calculator, title = {GDP Deflator Calculator — Nominal vs Real GDP Price Index}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/gdp-deflator-calculator}}, year = {2026}, note = {TG we-Calculate} }
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