Real GDP Calculator
Enter nominal GDP and the GDP deflator and the calculator returns real GDP, or give it any two of nominal GDP, real GDP and the deflator and it finds the third. Add several periods to see nominal growth, real growth and inflation side by side, with an optional population for real GDP per person. Free, no sign-up.
Your periods
Enter one or more periods in time order; with two or more you also get growth rates, each compared with the period before it. The deflator is 100 in the base year.
Results
Latest period: Year 3
4.76%
Real GDP growth
2.91%
Inflation (GDP deflator)
7.81%
Nominal GDP growth
Nominal GDP, real GDP and the deflator
| Period | Nominal GDP | Real GDP | GDP deflator | Real GDP per person |
|---|---|---|---|---|
| Year 1 | $20,000 billion | $20,000 billion | 100 | $60,606.06 |
| Year 2 | $21,630 billion | $21,000 billion | 103 | $63,253.01 |
| Year 3 | $23,320 billion | $22,000 billion | 106 | $65,868.26 |
Growth from the previous period
| Period | Nominal growth | Real growth | Inflation | Real per-person growth |
|---|---|---|---|---|
| Year 1 | — | — | — | — |
| Year 2 | 8.15% | 5% | 3% | 4.37% |
| Year 3 | 7.81% | 4.76% | 2.91% | 4.13% |
Working for Year 3
Real GDP = nominal GDP ÷ (deflator ÷ 100) = 23,320 ÷ (106 ÷ 100) = 22,000
Real growth = (22,000 − 21,000) ÷ 21,000 = 4.76%
Inflation = (106 − 103) ÷ 103 = 2.91%
Check: (1 + real growth) × (1 + inflation) = 1.0476 × 1.0291 = 1.0781 = 1 + nominal growth
Show the graph data as a table
| Period | Nominal GDP | Real GDP |
|---|---|---|
| Year 1 | 20,000 | 20,000 |
| Year 2 | 21,630 | 21,000 |
| Year 3 | 23,320 | 22,000 |
Real GDP is measured in the prices of the base year, where the deflator is 100, so in that year real and nominal GDP are equal. Agencies such as the BEA use chained dollars, which change the base more often; the identities above still hold.
How to Use the Real GDP Calculator
- 1. Choose what you have. Nominal GDP with the deflator gives real GDP; real GDP with the deflator gives nominal GDP; nominal with real GDP gives the deflator.
- 2. Set the currency and units. Pick a currency and say whether you are entering GDP in millions, billions or trillions. The unit labels the output and scales real GDP per person; it never changes a growth rate.
- 3. Enter your periods. Name each period (a year or a quarter), type the two known values, and optionally the population. Add more periods with the button, up to eight.
- 4. Read the results. The table fills in the missing quantity for every period, the growth table compares each period with the one before, and the working shows the formulas with your numbers.
Nominal GDP, Real GDP and the Deflator
Nominal GDP is the market value of all final goods and services produced in a period, measured at that period's prices. It can rise because output grew or simply because prices rose. Real GDP removes the price effect by valuing output at the prices of a fixed base year, so changes in real GDP reflect changes in quantities. The GDP deflator is the price index that connects the two, defined to be 100 in the base year. Principles of Macroeconomics from OpenStax and the U.S. Bureau of Economic Analysis (BEA) define them the same way.
The three formulas
Real GDP
Nominal GDP ÷ (GDP deflator ÷ 100)
Nominal GDP
Real GDP × (GDP deflator ÷ 100)
GDP deflator
(Nominal GDP ÷ Real GDP) × 100
Growth rate
(this period − last period) ÷ last period
Worked Example: Three Years of an Economy
The calculator opens with this example, in billions of dollars. Nominal GDP is 20,000 in Year 1 (the base year, deflator 100), 21,630 in Year 2 (deflator 103) and 23,320 in Year 3 (deflator 106).
| Period | Nominal GDP | Deflator | Real GDP | Nominal growth | Real growth | Inflation |
|---|---|---|---|---|---|---|
| Year 1 | 20,000 | 100 | 20,000 | — | — | — |
| Year 2 | 21,630 | 103 | 21,000 | 8.15% | 5% | 3% |
| Year 3 | 23,320 | 106 | 22,000 | 7.81% | 4.76% | 2.91% |
In Year 2, real GDP = 21,630 ÷ 1.03 = 21,000. Nominal GDP grew 8.15%, but about 3 points of that was higher prices, so real output grew only 5%. The three growth rates obey an exact identity: (1 + real growth) × (1 + inflation) = 1 + nominal growth, so 1.05 × 1.03 = 1.0815. The shortcut real growth ≈ nominal growth − inflation (8.15 − 3 = 5.15) is close but not exact, and the gap widens when inflation is high.
Real GDP per Person
Real GDP per capita divides real GDP by population and is the usual measure of changes in average material living standards. If the population in the example is 330, 332 and 334 million, real GDP per person is about $60,606, $63,253 and $65,868, so per-person growth in Year 2 is 4.37%, a little less than the 5% growth of the economy as a whole, because population grew too. Enter the population in the same period as the GDP figure.
Things to Watch
- The base year matters. Real GDP figures are only comparable when they share a base. The calculator assumes the deflator you enter is already on one base, with the value 100 in the base year.
- Chained dollars. The BEA reports real GDP in chained dollars, which update the price weights each year; for that reason the components of real GDP do not add exactly to the total. Growth rates from the BEA's own tables are the ones to cite for official figures.
- Quarterly figures are annualized. The BEA's headline GDP growth is the quarter-to-quarter change expressed at an annual rate. Enter annual figures here, or treat each row as one quarter and read the growth as a quarterly rate.
- Deflator versus CPI. The GDP deflator covers everything produced domestically and its basket changes with output; the consumer price index tracks a fixed basket of what households buy.
Frequently Asked Questions
- How do you calculate real GDP from nominal GDP?
- Divide nominal GDP by the GDP deflator and multiply by 100. With nominal GDP of 21,630 and a deflator of 103, real GDP is 21,630 ÷ 103 × 100 = 21,000. The result is in the prices of the base year, where the deflator equals 100.
- What is the GDP deflator formula?
- GDP deflator = (nominal GDP ÷ real GDP) × 100. It measures the average price of everything produced in the economy relative to the base year, so a deflator of 106 means prices are 6% higher than in the base year.
- How do you calculate the real GDP growth rate?
- Find real GDP for both periods, then compute (real GDP now − real GDP before) ÷ real GDP before. Growth in real GDP, not nominal, is the standard measure of how fast the economy is expanding, because it strips out inflation.
- How do you calculate inflation from the GDP deflator?
- Take the percentage change in the deflator between periods: (deflator now − deflator before) ÷ deflator before. A deflator that rises from 103 to 106 means inflation of 2.91%.
- Why is real GDP different from nominal GDP?
- Nominal GDP uses current prices, so it grows when prices rise even if output does not. Real GDP uses constant prices, so it moves only when the quantities of goods and services change. In a year of deflation, real GDP can be lower than nominal GDP.
- What is a good GDP per capita growth rate?
- There is no single threshold. Sustained real GDP per capita growth of 2% a year doubles living standards in about 35 years, and rich countries have typically grown at roughly that pace over long periods. Compare it with the same country's past and with similar economies.