What is the difference between nominal and real value?

Nominal value is the face amount of money; real value is what it can actually buy after accounting for inflation. Money can grow nominally while its real value falls if prices rise faster.

How does inflation erode purchasing power?

By raising the general price level over time, so each unit of money buys less. A balance that stays the same, or grows slower than prices, can purchase less than it used to.

Does saving protect me from inflation?

Only if the return beats inflation. A savings rate above the inflation rate grows real purchasing power; a rate below it means your money still loses value in real terms.

Why is inflation called a tax on cash?

Because it quietly reduces the purchasing power of money you hold, even though the face value is unchanged — like a levy on idle cash that no one hands you a bill for.

Inflation & Purchasing Power

See how inflation quietly erodes what your money can buy — and whether saving keeps up.

Understand why money loses value over time and how inflation differs from nominal growth.

Nominal vs. real value
Inflation rate
Rule of 70
Purchasing power

Guided walkthrough

Step 1 of 3

Predict first

Raise annual inflation from 3% to 6%.

Before you act, predict what will happen. Does the time for your money to lose half its value get cut roughly in half? Then do it — did your prediction match what happened?

Starting amount

Annual inflation

Savings rate (nominal)

Years

What your money is worth over time

Purchasing power of cash falls as prices rise; a nominal savings balance climbs in dollars — but those dollars buy less each year.

What is inflation and how does it erode purchasing power?

Inflation is a sustained rise in the general level of prices, which means each unit of money buys a little less over time. That gap between how much money you have and what it can actually buy is the difference between nominal and real value. A salary or savings balance can grow in nominal terms — the number gets bigger — while its real value, what it can purchase, shrinks if prices rise faster. This is why inflation is often called a quiet tax on cash: money left sitting loses purchasing power even though its face value never changes. A handy shortcut, the rule of 70, estimates how long it takes for prices to double, or for money's value to halve: divide 70 by the annual inflation rate. At 7% inflation, prices double in about a decade. To come out ahead, the return on savings has to beat inflation — a nominal interest rate below the inflation rate still leaves you poorer in real terms. Understanding the nominal-versus-real distinction is the key to seeing through the illusion that a bigger number always means more wealth.

How the simulation shows it

You set a starting amount, an inflation rate, a savings return, and a horizon, then watch the nominal balance and its real purchasing power diverge — the purchasing-power line sliding toward half its value as the years pass. Racing your savings rate against inflation yourself shows when saving keeps up and when it quietly falls behind.

Common misconceptions

A bigger number isn't always more money. If prices rise faster than your balance, its nominal value grows while its real purchasing power shrinks — you can have more and afford less.
Cash isn't risk-free. Money left idle loses value to inflation every year even though its face value never changes — that erosion is a real cost of doing nothing.
Beating inflation isn't automatic. A savings return below the inflation rate still leaves you poorer in real terms; only a return above inflation actually grows what your money can buy.

Frequently asked questions

What is the difference between nominal and real value?: Nominal value is the face amount of money; real value is what it can actually buy after accounting for inflation. Money can grow nominally while its real value falls if prices rise faster.
How does inflation erode purchasing power?: By raising the general price level over time, so each unit of money buys less. A balance that stays the same, or grows slower than prices, can purchase less than it used to.
What is the rule of 70?: A shortcut for how long prices take to double, or money's value to halve: divide 70 by the annual inflation rate. At 7% inflation, that's about ten years.
Does saving protect me from inflation?: Only if the return beats inflation. A savings rate above the inflation rate grows real purchasing power; a rate below it means your money still loses value in real terms.
Why is inflation called a tax on cash?: Because it quietly reduces the purchasing power of money you hold, even though the face value is unchanged — like a levy on idle cash that no one hands you a bill for.