Inflation Is Eating Your Savings — Here's the Math

This used to be a back-of-the-envelope job. Now it is one tap, but the logic has not changed. Cash feels safe. It isn't. Even a 'low' 3% inflation rate halves your money's spending power in just 24 years.

The rule of 72 (inflation edition)

Divide 72 by inflation. 3% inflation halves your money in 24 years. 6% in 12. 9% in 8.

Why savings accounts lose real value

If your account pays 2% and inflation runs 4%, you lose 2% in real purchasing power each year — even though the number on the screen rises.

What beats inflation historically

Equities (long term), real estate, inflation-linked bonds, commodities (in spurts). Cash and traditional bonds usually do not.

The cost of waiting

$10,000 'safely' under the mattress for 30 years at 4% inflation = ~$3,080 in today's purchasing power. The 'safe' choice destroys 70% of the value.

Pro tips

• Hold only your emergency fund in cash. Everything beyond it should be working.
• Use inflation-adjusted (real) returns when planning long-term goals.

Frequently asked questions

What's the historical average inflation? US: ~3% over 100 years. Many emerging markets: 7–15%. Always plan against local data.

Are crypto and gold real inflation hedges? Gold sort-of, over decades. Crypto has too short a history to call.

Bookmark the calculator linked above — you will need it more often than you think.