Investing term

What is Inflation?

The gradual loss of purchasing power over time. $100 buys less each year.

Inflation is the gradual rise in the general level of prices, which means each unit of your money buys a little less over time. At a typical 2–4% a year it feels invisible day to day, but it compounds like interest in reverse — over a few decades it can halve what a fixed sum of cash will buy.

Inflation is the quiet reason investing isn't optional. Money left in a low-interest account doesn't just fail to grow; it actively loses real value every year prices rise faster than it earns. To simply stay even you need a return at least equal to inflation, and to build wealth you need to beat it.

How inflation erodes cash
$0$25$50$75$100today5 yrs10 yrs$74what $100 can buyAt 3% inflation, idle cash loses about a quarter of its value in a decade.

At 3% a year, the buying power of $100 falls to about $74 over a decade. The dollars are unchanged; what they can buy quietly shrinks.

For example

At 3% inflation, $100 today buys only about $74 worth of goods in ten years — cash that just sits there is quietly getting poorer.

Learn it by doing

That's Inflation in theory — it clicks when you use it. Practise it hands-on in a free, interactive lesson (Stage 1, Money, Goals & Your Financial Foundation).

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Why it matters to you

Inflation reframes what "safe" means: cash feels risk-free because its number never drops, yet it's guaranteed to lose buying power whenever it earns less than prices rise. That makes doing nothing a slow, certain loss — the opposite of safe. It's also why long-term returns should always be judged after inflation, and why assets that tend to grow with the economy, like stocks, are the usual defence against it.

Cash feels safe but silently shrinks

The figure in a savings account never falls, so it feels like the safest possible place. But if it earns 1% while inflation runs 3%, you're losing 2% of real buying power a year with total certainty. "Safe" in nominal terms can mean a guaranteed loss in real terms — the risk is just harder to see.

Frequently asked questions

What causes inflation?

Broadly, prices rise when demand outpaces supply or when the cost of producing goods climbs — for example from higher wages, energy prices, or an expanding money supply. Central banks try to keep inflation low and steady, often around a 2% target, by adjusting interest rates.

Is some inflation good?

Most economists think mild, predictable inflation — around 2% — is healthier than none, because it encourages spending and investment and gives central banks room to cut rates in a downturn. The danger is high or unpredictable inflation, which erodes savings and makes planning hard.

How do I protect my money from inflation?

Hold long-term money in assets that tend to grow at least as fast as prices — broadly diversified stocks are the common choice, and some investors add inflation-linked bonds or real assets. The key is not leaving long-term money in cash, where inflation erodes it with certainty.

What's the difference between inflation and cost of living?

Inflation is the rate at which prices rise across the economy; the cost of living is the actual amount you need to spend to maintain your lifestyle. Inflation pushes the cost of living up over time, but your personal cost of living also depends on where you live and what you buy.

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Related terms

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