Retirement Calculator

What is a retirement calculator?

A retirement calculator projects how much a current account balance plus regular monthly contributions will grow to by retirement age, using compound returns. The result is a planning figure — not a guarantee — for deciding how much to save each month.

How this calculator works

• Enter your current age, retirement age, existing balance, and monthly contribution.
• Pick an annual return before fees — a common long-run assumption for a broad stock portfolio is 7%, but use a number you can defend.
• Enter expected inflation so you can see the future balance in today’s dollars, not just nominal dollars.
• It compounds monthly, the way most 401(k)s and superannuation accounts accrue.

How to use the result

1. Compare the nominal future value with the inflation-adjusted number. The inflation-adjusted one is the real purchasing power you should plan around.
2. Divide the inflation-adjusted figure by your expected years in retirement to sanity-check whether it covers living costs.
3. If the number looks short, raise the monthly contribution and re-run — a small increase early compounds enormously.
4. Treat the estimated monthly income as a rough annuity equivalent, and add expected Social Security, pension, or other income on top.

How much do I need to save for retirement?

There is no single number, but a widely used rule of thumb is to aim for 10–15% of gross income saved annually across all accounts, starting early. The calculator lets you work backward: pick a target income, see what balance produces it, then find the monthly contribution that reaches that balance. Fees, taxes, and variable markets mean your actual path will differ, so re-run the projection yearly.

Common mistakes

• Using an unrealistically high return. Assuming 12% when long-run broad-market averages run closer to 7–10% overstates the balance substantially.
• Ignoring inflation. A million dollars in 2050 buys far less than a million today; the inflation-adjusted number is the honest one.
• Forgetting fees. If your fund charges 1% in fees, subtract roughly that from the return you enter.

Retirement is the compounding side of the same math that drives a lump-sum investment growth projection once you have the balance saved. If you’re still paying off debt, compare the growth you’re giving up against the interest you’re paying first.