Investment Calculator With Withdrawals

Most compound-interest calculators only add money. This one subtracts it. Enter a balance, a monthly withdrawal and a return rate to see whether the investment grows, holds steady, or runs down — and when.

Growth with withdrawals: the break-even rate

An investment with monthly withdrawals has a simple tipping point. If the annual return exceeds the annual withdrawal rate plus inflation, the real balance grows forever; if it falls short, the balance eventually hits zero. With the default above — $300,000, $1,000 a month (4%/yr), 7% return, 2.5% inflation — growth wins and the result is "indefinitely." Change the return to 5% and the money runs out after roughly 38 years. The calculator makes that threshold visible instantly.

How the calculator works

Each month the balance earns one month of return, then the withdrawal is taken out. Every 12 months the withdrawal is increased by the inflation rate so your spending power stays level. If you enter a tax rate, each withdrawal is grossed up so the after-tax amount you keep matches the number you typed. The calculator stops when the balance hits zero, or after 100 years if it never does.

The "to last 20 / 25 / 30 years" figures are solved by bisection: the largest starting withdrawal that still survives that horizon under the same return and inflation assumptions.

Common uses

• Living off dividends or interest. Enter the portfolio's total return, not just the yield, and the withdrawal you take. If the result is "indefinitely," you are living within the portfolio's means.
• Funding college from a brokerage account. Set inflation to 5–6% (tuition inflation) and a 4-year horizon, and see what balance is needed.
• A trust or inheritance paying a monthly stipend. The "to last N years" figures show the sustainable stipend for a chosen term.
• Early retirement (FIRE). Use a 40–50-year horizon by checking whether the result is "indefinitely" at a 3–3.5% withdrawal; that is the FIRE community's working definition of a safe rate.

Choosing realistic inputs

• Annual return. 4–5% is a conservative planning number for a balanced portfolio; 6–7% is closer to long-run history for 60/40; cash and CDs are 3–5% today but fall when rates fall.
• Inflation. The Federal Reserve targets 2%; the 30-year U.S. average is about 2.5%. Healthcare inflation runs higher, so retirees with large medical costs should test 3–3.5%.
• Withdrawal. Use what you actually spend, minus guaranteed income (Social Security, pension, annuity). That net gap is what savings must cover.

Taxes on investment withdrawals

In a taxable brokerage account you are taxed on dividends and on realised gains, not on the full withdrawal — selling $1,000 of stock with a $600 cost basis creates $400 of gain, taxed at 0%, 15% or 20% depending on income. The tax field in this calculator applies a flat rate to the whole withdrawal, which is right for traditional retirement accounts and conservative for brokerage accounts. For a taxable account, enter roughly half your capital-gains rate as an approximation.

SavingsLast calculators are educational estimates. They assume a constant average return and steady inflation; real markets are volatile and sequence-of-returns risk can shorten how long money lasts. Nothing here is financial, investment, tax, or legal advice. Consult a qualified professional before making decisions.