How to correct an amount with IGP-M
Enter the BRL amount paid and the purchase month. The calculator multiplies the official monthly IGP-M factors between the starting and ending months.
The period defaults to the latest complete month in the snapshot. Choose an earlier ending month to reproduce a historical correction.
What would a property purchase amount be after IGP-M correction?
The result expresses a historical amount after IGP-M monetary correction and can be an educational reference for comparing purchasing power between months.
It does not mean the property would sell for that amount. A broad price index and Brazil's property market can follow very different paths.
IGP-M is not property appreciation
IGP-M is a broad FGV price index. The IGP family combines 60% IPA, 30% IPC, and 10% INCC; it does not directly measure residential sale prices.
A market appraisal would require comparable location, area, standard, condition, and recent transaction data.
How accumulated IGP-M between dates is calculated
For each month, the factor is one plus the percentage rate divided by 100. All factors are multiplied without adding percentages or rounding intermediate values.
Both endpoint months are included. If they are equal, one monthly rate is applied, including a negative rate.
Which IGP-M series does the calculator use?
It uses Brazilian Central Bank SGS series 28655, identified by the Citizen Calculator methodology for IGP-M corrections consistent with FGV index-number precision.
Series 189 publishes rounded monthly rates, so calculators based on it may show a small accumulated difference.
Why does correction start in July 1994?
The amount field is in Brazilian reais. Older historical observations exist, but amounts originally paid in earlier currencies require a separate currency conversion.
The tool starts with the Real Plan to avoid mixing cruzado, cruzeiro, and real values.
Official data through August 2026
The snapshot contains 447 contiguous monthly series 28655 observations from June 1989 through August 2026, retrieved on August 29, 2026.
Updates run server-side and are version controlled. The browser does not call the Central Bank or FGV while calculating.
Official sources and methodology
Review the methodology, series, and limitations directly with the responsible Brazilian institutions.
Related calculators
Explore housing, financing, and interest scenarios without confusing future assumptions with historical correction.
Important notice
This educational tool applies monetary correction using the stated historical IGP-M series. The result is not an appraisal, report, sale price, contractual calculation, or legal, accounting, or tax advice.
Location, property features, renovations, condition, supply, and demand may make the actual price move very differently. Consult professionals and official sources for important decisions.
Frequently asked questions
Does this show what my property is worth today?
No. It only shows the original amount corrected by IGP-M through the selected month. A market appraisal needs property and comparable-sale data.
Does IGP-M measure property appreciation?
No. IGP-M is a broad Brazilian FGV price index, not a residential sale-price index.
Is the purchase month included?
Yes. The method includes both starting and ending months. A one-month interval applies that month's rate.
Why can the result decrease?
Some months have negative IGP-M. If deflation dominates the selected interval, the factor can fall below one and the nominal difference becomes negative.
Why can another IGP-M calculator differ?
This tool uses higher-precision series 28655. Calculations based on rounded series 189 rates can accumulate small differences.
What is the latest IGP-M month used?
The current snapshot ends in August 2026. Its date appears with the result and changes when a new official month is bundled.
Can I correct values from before the Real Plan?
Not here. The input is BRL and starts in July 1994 to avoid incorrectly interpreting older currencies.
Can I use this for a contract, lawsuit, rent, or tax?
Use it only as an educational reference. Contracts and legal, accounting, and tax rules can require different indices, dates, interest, and criteria.