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Future Cost & Purchasing Power

Inflation Calculator — Future Cost & Purchasing Power

Two different questions, one tool: what will today's expense cost you later, or what is a fixed sum of money really worth after inflation erodes it? Pick a mode below.

📈 Future Cost of an Expense

Formula: Future Cost = Today's Amount × (1 + Inflation)ⁿ

💡 Result

Enter values and click Calculate
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Disclaimer: This calculator is for educational purposes only and does not constitute financial advice. It assumes a constant inflation rate, which real inflation rarely follows exactly. Actual future costs and purchasing power will vary. Consult a licensed financial advisor for personal planning decisions.

Future Cost vs Purchasing Power — Two Sides of the Same Coin

Mode A — Future Cost: You have a recurring expense or goal today (school fees, a wedding budget, your monthly lifestyle cost). This mode tells you what that same thing will cost in the future, so you can plan and save for the real number, not today's number.

Mode B — Purchasing Power: You're holding a fixed sum that isn't growing — cash, a low-interest account, an insurance payout. This mode tells you what that fixed sum will actually be able to buy in the future, in today's terms, after inflation quietly erodes it.

Both use the identical compounding formula, just applied in opposite directions — one grows a future cost, the other shrinks a fixed sum's real value.

The Formulas

Future Cost = Today's Amount × (1 + Inflation)ⁿ

Real Purchasing Power = Fixed Amount ÷ (1 + Inflation)ⁿ

Where n is the number of years. The Rule of 70 estimates doubling/halving time: Years to Halve ≈ 70 ÷ Inflation Rate(%).

Worked Example

You spend ₹50,000/month today. At 6% inflation over 10 years: Future Cost = 50,000 × (1.06)10 = ₹89,542 — nearly 79% more than today, for the exact same lifestyle.

Conversely, if you kept ₹50,000 in cash instead of spending it, in 10 years at 6% inflation it would only buy what ₹27,919 buys today — a real purchasing power loss of over 44%.

How Inflation Rate Changes the Outcome (₹50,000 today, 10 years)

Inflation RateFuture CostPurchasing Power of ₹50,000Years to Halve
4%₹74,012₹33,77817.5 years
6%₹89,542₹27,91911.7 years
8%₹1,07,946₹23,1608.75 years

Frequently Asked Questions

Future cost asks: what will today's expense cost me later? The number goes up. Purchasing power asks: what is a fixed amount of money I'm holding really worth later, in today's terms? The number goes down. Both use the same inflation math, applied to opposite questions.
India's long-run CPI inflation has commonly averaged in the 5-7% range, though it varies by year and category — education and healthcare inflation often run higher than headline CPI. Many planners use 6% as a general working assumption; adjust based on your own expense categories.
The Rule of 70 estimates how many years it takes for a value to double (or halve) at a given growth rate: divide 70 by the annual rate. At 7% inflation, purchasing power roughly halves in 70 / 7 = 10 years.
Cash and low-interest savings accounts typically lose purchasing power to inflation over time. Assets that have historically outpaced inflation over long periods include equities, real estate, and inflation-linked instruments — though all carry their own risks and none are guaranteed.