Inflation-adjusted Retirement Calculator

Real return = (1 + nominal return) ÷ (1 + inflation) − 1 (Fisher). Savings grow at the real return; expenses stay constant in today’s money; the corpus and income are in today’s purchasing power. Nominal = real × (1 + inflation)^years.

Why plan in real terms

Nominal numbers mislead. A projection that ends with “$2.3 million” feels like wealth, but if it’s 30 years away, inflation has shrunk what it buys to a fraction. Planning in real terms fixes that: by using the real return — roughly your nominal return minus inflation, via the Fisher equation — every figure stays in today’s money, directly comparable to the spending you understand now. The calculator still shows the nominal numbers alongside, so you can see both the big future figure and what it’s actually worth.

Worked example — age 35, retiring at 65, $50,000 of expenses, $100k saved, $1,000/month, 7% return, 2.5% inflation: The real return is about 4.4%. Your projected corpus is ~$1.08M in today’s money (≈ $2.27M nominal), against ~$783k needed — a real surplus. That same $50,000 of spending will cost about $105,000 a year in nominal terms by 65.

The pension-indexing swing

Whether your other income keeps pace with inflation changes the picture dramatically. An index-linked pension or Social Security holds its real value, so it reliably offsets your expenses every year. A fixed nominal pension does not — its purchasing power erodes, so in real terms it covers less and less, and your corpus has to make up a growing gap. The calculator shows the corpus you’d need under the opposite assumption, so you can see exactly how much that one feature is worth — often tens of thousands of dollars of required savings.

Reading the result

The headline is your real surplus or shortfall: projected corpus minus what you need, in today’s money. Positive means you’re on track; negative means you need to save more, work longer, spend less, or earn a higher return. The “real income it supports” shows the spending your projection actually sustains. The chart makes the inflation story visible — the nominal balance climbs steeply while the real balance, in today’s purchasing power, tells the truer story. Like all projections it assumes steady returns and ignores sequence-of-returns risk.