Terra Investor Tools — Down to Earth. Smarter Investing.
Free Financial Calculator · Retirement income

Retirement Balance-to-Income Calculator

Translate a 401(k), IRA or retirement portfolio balance into a first-year monthly-income estimate, add Social Security and pension income, then stress-test how the portfolio behaves over time.

Reviewed · Sep 23, 2026
What this does

Shows first-year portfolio income, total monthly income before taxes, your spending gap or surplus, and a deterministic inflation-adjusted withdrawal projection.

What it does not do

It does not model taxes, RMDs, Social Security claiming strategy, market volatility or survivor planning. Use the Retirement Income Planner for those deeper layers.

Terra approachBalance → incomeReliable income + portfolio incomeStress-test, don’t predictRead the decision guide →

Your assumptions

Use today’s dollars for the monthly Social Security, pension and spending inputs. The projection increases the portfolio withdrawal by your inflation assumption each year.

Use your own SSA estimate when available.
Smooth annual return for stress testing, not a market forecast.

Saved scenarios stay privately in this browser under My Terra.

Method: annual deterministic projection. Terra applies the entered annual return to the opening balance, then subtracts that year’s withdrawal; the withdrawal rises annually with inflation. Social Security and pension income are shown in the first-year income picture but are not deposited into the portfolio model.