Inflation Calculator: Calculate Price Increase over a Period of Time

This inflation calculator 2026 allows you to compare prices or assets from the past with values from subsequent years on a monthly basis. The calculations are based on the official consumer price index (CPI) for Germany.

How would your salary need to change to offset inflation? Let's assume you received a monthly salary of €2,300 in 2020. To offset inflation, your salary would have to rise to €2.804 in 2025. Enter your values in the inflation calculator. Did you buy shares in previous years? Then you can compare the development of the share value with the general price development. Or suppose you purchased real estate in previous years. How high could the price of this property be in 2026 as a result of inflation alone? However, it should be noted that the result generally does not correspond to the current market price of the property. This may be higher or lower and depends heavily on property price trends, the location, and the situation of the property.

Calculate Index-Linked Rent on a monthly basis using the Inflation Calculator

In the case of an index-linked rent, the parties to a lease agreement under Section 557b of the German Civil Code (BGB) may agree in writing that the rent will be determined by the cost-of-living index for all private households in Germany (Consumer Price Index, CPI) as calculated by the German Federal Office of Statistics. With this Inflation calculator 2026 you can calculate the current rent increase due to inflation (rising CPI) or a rent decrease due to deflation (falling CPI) with monthly precision. To perform a calculation with monthly precision, the “Use annual values” option must be deselected. To calculate the current rent adjustment for an index-linked rent, enter the rent since the start of the lease or since the last index-based rent adjustment as the base value for the first year, specifying the month. The last year, also specified by month, indicates the desired date for calculating the adjusted rent. An estimate for future years can also be calculated.

Inflation calculation in German family law

Let’s say you got married in 2002 and had assets worth 10,000 euros. How much will those assets be worth in 2026? With this calculator, you can determine the real value of your assets on a month-by-month basis using Germany’s official consumer price index (CPI) in Germany. After a divorce, when calculating the Equalization of Accrued Gains, you must take into account how inflation has affected the value of your assets. The original assets you brought into the marriage on your wedding day change over time in line with the inflation rate.

Inflation Calculator 2026 online

The price increase for a selected period can be calculated on a monthly basis or based on the annual average inflation rate. If you want to use the annual average inflation rate, select "Use annual Values". To calculate the price increase on a monthly basis, deselect "Use annual Values". Enter the first and last years to define the period to be considered. If “Use annual values” is selected, the months must also be specified. The shortest period that can be considered is one year. For the first year, enter the value whose performance is to be analyzed. The calculated value for the last year indicates by how much the value of the first year has increased due to inflation or, if applicable, decreased due to deflation. As additional information, the current Consumer Price Index () for the first and last year, relative to the base year 2020 You can select whether the values should be entered or displayed in euros (€) or German marks (DM).

The maximum value for the first year is the current year 2026. If the entered first or last year is the current year 2026, the inflation rate and the Consumer Price Index (CPI) for that year are calculated based on the most recently published monthly inflation rates. If the entered last year is later than the current year 2026, the inflation rate for the coming years is estimated. In this case, a note is displayed with the years used for the estimate.

Enter current values and select [Calculate]:

Related to the value entered in the first year, the purchasing power indicates the real value at the end of the last year. The calculated price rise is defined as the percentage change in prices between the starting and ending date of the relevant period. The average inflation rate per year indicates the percentage by which the prices have risen on an average per year. Negative percentage values indicate deflation in the period under review (1948–1950, 1953, and 1986). Last year's inflation rate indicates by how many percent prices have increased from the beginning to the end of last year. For the years after 2026 onwards, last year's inflation rate is the estimated value.

How to calculate average inflation rate per year

The average inflation rate spent per year applied to the amount in the first year and in each case to the resulting price increases of all subsequent years results in the amount spent in the last year. The average inflation rate per year I is calculated from the geometric mean of all consumer price indices (CPI) in the period under consideration over n years with i = 1 ... n:

x_i = CPI_i+1 / CPI_i
I = ((x₁ * x₂ * ... * x_n) ^1/n) - 1) * 100.

For the years 2017 to 2020, for example, n = 3 results in an average inflation rate I of:

x₁ = CPI₂₀₁₈ / CPI₂₀₁₇ = 98,1 / 96,4 = 1,0176
x₂ = CPI₂₀₁₉ / CPI₂₀₁₈ = 99,5 / 98,1 = 1,0143
x₃ = CPI₂₀₂₀ / CPI₂₀₁₉ = 100,0 / 99,5 = 1,0050
m = x₁ * x₂ * x₃ = 1,0373
I = (m^1/n - 1) * 100 = 1,23 %

The average inflation rate of 1.23% applied to the value of € 1,000 in the first year and to each of the following 2 years results in a price increase of € 1,037.35 in the last year:

2018: 1.23 % von € 1,000.00 = € 12.30
2019: 1.23 % von € 1,012.30 = € 12.45
2020: 1.23 % von € 1,024.75 = € 12.60

This results in a price increase of € 1,024.75 + € 12.60 = € 1,037.35. Due to rounding errors, a small deviation occurs compared to the result from the calculation of the price rise from the consumer price index (CPI).

Estimation of the inflation rate for coming years

If the last year entered in the inflation calculator is later than the year 2026, the inflation rate for the coming years is estimated. For this purpose, the historical consumer price indices (CPI) of the past years are used according to the number of future years. For this past period, the average inflation rate per year and the resulting consumer price index (CPI) for the most recent year are output. In the case of estimated data, a note is displayed in the inflation calculator with the annual figures used for the estimate.