Retirement Calculator

Retirement planning comes down to two numbers: how much you will need when you stop working, and how much you are on track to have. This calculator works out both, shows the gap, and includes your 401(k) employer match and a Roth vs traditional comparison.

How to use the retirement calculator

1. Enter your ages. Your current age, the age you plan to retire and the age the money has to last until. Planning past your average life expectancy, to 90 or 95, is the safer choice.
2. Add what you have and what you save. Retirement savings today, your monthly contribution, your salary and the raise you expect each year. Your contribution rises with your salary, so it stays the same share of your pay.
3. Fill in the employer match. For example 50% on contributions up to 6% of salary. Set it to 0 if you have no match.
4. Set the assumptions. Returns before and after retirement, inflation, the yearly income you want and what Social Security or a pension will pay, both in today’s money.
5. Read the results — target, projected savings, shortfall or surplus, the extra monthly saving needed and the age the money lasts until.

How it works

The savings target is the lump sum that funds your income for every year of retirement. Each year’s withdrawal rises with inflation and is taken at the start of the year, so the target is the present value of a growing annuity due:

income from savings  = wanted income − Social Security & pensions
real return          = (1 + return in retirement) / (1 + inflation) − 1
target (today's $)   = income × (1 − (1 + real)^−N) / real × (1 + real)
target at retirement = target (today's $) × (1 + inflation)^years to retirement

N is the number of years in retirement. The projection runs month by month at your return before retirement divided by 12, with contributions and the match deposited at the end of each month:

The drawdown check then spends the projected balance year by year to show the age your money lasts until.

The Roth vs traditional comparison looks only at your own contributions at the same take-home cost. A traditional contribution of C costs C × (1 − tax now) of take-home pay and is taxed at your retirement rate when you withdraw it. The same take-home pay buys a Roth contribution of C × (1 − tax now) that comes out tax-free. Both grow at the same rate, so the account that wins is the one with the lower tax rate.

Worked examples

A 35-year-old using the defaults. 50,000 saved, 500 a month on a 75,000 salary, 2% raises, a 50% match up to 6%, 7% before retirement, 5% after, 2.5% inflation. They want 60,000 a year from 67 to 92 and expect 24,000 from Social Security, leaving 36,000 to cover.

The first-year match is 2,250: half of 4,500, which is 6% of 75,000.

A 45-year-old with a gap. 80,000 saved, 400 a month on 90,000, no raises, a 50% match up to 6%, 6% before retirement, 4% after, and inflation set to 0 so everything is in today’s money. They want 70,000 a year from 67 to 90, with 26,000 from Social Security.

• Income from savings: 70,000 − 26,000 = 44,000 a year for 23 years.
• Target: 44,000 × 15.451 (the annuity-due factor at 4% for 23 years) ≈ 679,849.
• Monthly deposit: 400 + a 200 match (half of 4,800, below the 5,400 cap) = 600.
• Projection over 264 months at 0.5%: 80,000 grows to about 298,490 and the deposits to about 327,736, a total of about 626,226.
• Shortfall: about 53,623. The savings run out around age 87.
• Saving about 98 more a month closes the gap.

Roth vs traditional. In the first example, 22% tax now and 12% in retirement. The 500 a month grows to about 882,559 pre-tax. Traditional leaves about 776,652 after 12% tax; Roth at the same take-home cost leaves about 688,396. Traditional wins by about 88,256 — 10% of the balance, the gap between the two tax rates.

Common mistakes

• Mixing today’s money and future money. A 1.5 million target 30 years from now is far less in today’s terms. Compare like with like.
• Leaving match money on the table. Contributing less than the match cap gives up an instant return of 50–100%.
• Assuming a high return for decades. Try your plan at 5% as well as 7%.
• Forgetting taxes on traditional withdrawals. Pre-tax balances are not all yours to spend.
• Planning to an average lifespan. Many people live well past the average, and running out late is the hardest problem to fix.

401(k) contribution limits

For 2026 the IRS lets employees defer up to 24,500 into a 401(k), plus an 8,000 catch-up from age 50 (32,500 in total) or an 11,250 catch-up at ages 60 to 63 (35,750), according to IRS Notice 2025-67. When the currency is USD, the calculator warns you if your yearly contribution is above the limit for your age. The employer match does not count toward this limit.

These results are estimates from a constant-return model, not financial or tax advice. Real markets swing from year to year, and fees, taxes and the timing of bad years all change the outcome. A fee-only financial planner can help you test the plan.

Last reviewed: October 3, 2026