Purchasing power

Inflation calculator

Inflation is the reason a retirement number that looks generous today may not be. This runs it both ways: what today’s money will buy later, and what you would need later to match today.

The amount

Currency

Changes the symbol on your figures. It does not convert them — there is no exchange rate here.

Amount today

Inflation rate

Central banks in the US, UK and eurozone all target 2%. The long-run realised figure has been closer to 2.5–3%.

Number of years

What it will buy then, in today’s money

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Needed then to match

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Purchasing power lost

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Prices multiply by

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This calculator needs JavaScript to recalculate. The figures above are a worked example, and every assumption behind them is written out below.

What this assumes

A constant rate, compounded annually. Real inflation is neither, and a single average hides the years that did the damage — but a constant rate is the right tool for the question “roughly how much does this matter”.

Your own inflation rate is not the headline rate. It depends on what you buy: housing, energy and childcare have run well above average in most of these markets, and consumer electronics well below.

The two questions people arrive with

The first is “what will my savings be worth”, which is a division: 100,000 in twenty years at 3% buys about 55,000 of today’s goods.

The second is “what would I need”, which is a multiplication and gives a bigger, more alarming number: about 181,000 to buy what 100,000 buys now. Both are true and they are not the same figure — which is why this page shows them together.

Why every FIRE projection should be in today's money

A retirement projection in nominal terms produces impressive totals that quietly mean less than they look. Working in today’s money instead — deflating the return once, at the start, and leaving every figure downstream in current purchasing power — makes the answer directly comparable to your current spending.

That is what our FIRE calculator does, and it has a useful side effect: real arithmetic is identical in dollars, pounds and euros, so one calculation serves all three.

Common questions

What inflation rate should I use?

The Federal Reserve, Bank of England and European Central Bank all target 2%. Realised long-run inflation has been closer to 2.5–3% in each. Using 3% for planning is a reasonable, slightly cautious choice.

Does inflation affect my debts too?

Yes, and in your favour. A fixed-rate mortgage is repaid in money that is worth less each year, which is why long fixed-rate debt is less punishing in real terms than the headline balance suggests. Variable-rate debt gives you none of this, because the rate typically rises with inflation.

Is my personal inflation rate different?

Almost certainly. The published figure is a basket average. If a large share of your spending is rent, energy or childcare, your own rate has probably been well above it for the last several years.

The app this comes from

Inflation is measured against what you actually buy

The headline rate describes an average household. Yours is made of your own categories, and the only way to know whether energy or rent or groceries is the line moving your cost of living is to have a record of them.

Not out yet. TLDR Money International is in build for the United States and the United Kingdom first, on iPhone and Android. There is nothing to download and nothing to sign up to — when there is, this page will say so.

Last reviewed 20 August 2026. The arithmetic behind this page is covered by automated tests that run on every deploy.