DocomintCalculadora de Inflação
Calcule quanto um valor valerá no futuro, ou quanto vale hoje um valor do passado.
What is a Calculadora de Inflação?
Inflation compounds the same way interest does, just working against purchasing power instead of for it — this covers both directions: projecting what something will cost years from now at a given inflation rate, or the reverse, converting an old price or salary figure into what it's actually worth in today's money.
How to use the Calculadora de Inflação
- Choose whether you're projecting a future cost or converting a past amount to today's value
- Enter the amount, inflation rate, and number of years
- The adjusted value appears instantly, calculated on your device
Formula
Future Cost = Amount × (1 + rate/100)ᵗ | Past Value Today = Amount × (1 + rate/100)ᵗ
Both directions use the same compounding formula — the only difference is which end (today or the future/past) you're solving for.
Example
$1,000 today, projected forward at 3% annual inflation for 10 years, is expected to cost about $1,344 — meaning today's $1,000 has the same purchasing power as roughly $1,344 will have a decade from now, a useful sanity check when comparing an old salary offer to a new one.
Common mistakes
- Using a single unusually high or low year's inflation figure as the long-run assumption instead of a multi-year historical average.
- Mixing up "future cost" mode with "past value" mode — both use the same math but answer opposite-direction questions.
- Treating the result as a specific product's real price history rather than a general purchasing-power adjustment, which can diverge from any one item's actual price trend.
Frequently asked questions
What inflation rate should I use?
Historical long-run average inflation in many developed economies is roughly 2–3% annually, though it varies significantly by country and time period. Use your country's actual historical average, or a specific target rate, for a more realistic projection.
Why does a dollar today buy less in the future?
Because prices for goods and services tend to rise over time (inflation), the same nominal dollar amount buys fewer goods later than it does now — which is why comparing salaries or prices across different years needs an inflation adjustment to be meaningful.
Where can I find my country's historical inflation rate?
A government statistics agency or central bank typically publishes an official consumer price index (CPI) figure — search for your country's CPI inflation data for the most accurate historical rate to use here.
Is inflation the same every year?
No — the annual rate fluctuates, sometimes significantly, based on economic conditions. This calculator assumes one constant rate across the whole period for simplicity, which is a reasonable long-run approximation but won't match any single volatile year exactly.
Is my numbers uploaded anywhere?
No — Calculadora de Inflação runs entirely in your browser using JavaScript/WebAssembly. Your numbers is never sent to a server.