# GDP Deflator Calculator

URL: https://speedycalculator.com/calculators/finance/gdp-deflator/
Last updated: 2026-10-25

> The GDP deflator calculator works out the GDP price deflator from nominal and real GDP – a broad measure of inflation across the whole economy – and the inflation rate between two years.

## Inputs

- Nominal GDP
- Real GDP
- Last year's GDP deflator

## Results

- GDP deflator
- Inflation since last year
- Price level vs base year

## Formula

```
GDP deflator = nominal GDP ÷ real GDP × 100
Inflation = (deflator this year ÷ deflator last year − 1) × 100
Real GDP = nominal GDP ÷ deflator × 100
```

## Explanation

Unlike the CPI, the GDP deflator covers all goods and services produced domestically – including investment and government purchases – and its basket changes every year.

### How to use the GDP Deflator Calculator

- **Nominal GDP**
- **Real GDP**
- **Last year's GDP deflator**

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Enter nominal and real GDP for this year and, optionally, last year's deflator.

### Tips

- Use real (inflation-adjusted) figures to compare across years.
- Check whether data are seasonally adjusted.
- Use the same currency and base year throughout.
- Economic models simplify reality – treat results as illustrations, not forecasts.

### Common mistakes to avoid

- Mixing nominal and real values.
- Comparing percentage changes with percentage-point changes.
- Treating correlations as causes.

### Inputs explained

FieldWhat to enterNominal GDPAmount in your currencyReal GDPAmount in your currencyLast year's GDP deflatorA number

### What each result means

- **GDP deflator** = [Nominal GDP]÷[Real GDP]×100
- **Inflation since last year** = ([GDP deflator]÷[Last year's GDP deflator] - 1)×100
- **Price level vs base year** = [GDP deflator] - 100

### Example values

How the main result changes when **Nominal GDP** changes and everything else stays at the example values above:

Nominal GDPGDP deflator14,50061.721,75092.5529,000123.436,250154.2643,500185.1158,000246.81

## Worked example

Inputs — Nominal GDP: $29,000; Real GDP: $23,500; Last year's GDP deflator: 120.

Results — **GDP deflator = 123.4**; Inflation since last year = 2.84 %; Price level vs base year = 23.4 %.

## FAQ

**What is the GDP deflator?**
A price index for everything produced in the economy.

**How is it different from the CPI?**
It covers all domestic output, not just a consumer basket.

**What does a deflator of 120 mean?**
Prices are 20% higher than in the base year.

**What formula does the GDP Deflator Calculator use?**
GDP deflator = nominal GDP ÷ real GDP × 100.


## Sources

- [U.S. Bureau of Economic Analysis – GDP](https://www.bea.gov/data/gdp/gross-domestic-product)