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RetirementPlanCalc · US planning tools

FIRE Calculator

Estimate a financial-independence target and the time to reach it under a simplified constant-return savings scenario.

Free · No account required · Results below

Your planning inputs

How to use the fire calculator

  1. Enter your own balances, time period, and spending or contribution amounts. Keep today’s dollars and future dollars separate.
  2. Choose return and inflation assumptions. Returns should reflect fees. The default numbers are examples, not recommendations or forecasts.
  3. Select Calculate. Results appear below your inputs. Read the assumptions alongside the estimate.
  4. Try lower returns, higher inflation, and a longer retirement horizon where the tool allows it. Save your assumptions so you can compare scenarios.

How the calculation works

Target = annual spending ÷ withdrawal-rate fraction. Iterate monthly using an effective real return and a fixed real contribution until the balance reaches the target, or 100 years pass.

A simple example

At zero real return, a $1,000,000 target, $100,000 starting balance, and $1,500 monthly contribution require 600 months, or 50 years.

Read the result with care

A calculator can make a planning tradeoff easier to see. It cannot predict future investment returns, personal spending, tax rules, or how long you will need your money.

These projections use simplified assumptions. Account limits, tax treatment, investment risk, healthcare costs, and the timing of Social Security can change a real retirement plan. Check account and benefit details with their official providers.

If a result looks too optimistic, compare several scenarios and review the inputs. A model that works with constant returns can still fail when actual returns vary during withdrawals.

Frequently asked questions

Are the default return and inflation rates forecasts?

No. They are editable assumptions for examples. No live market, inflation, or account data is loaded.

Does this calculator include taxes or account limits?

No. Review taxes, eligibility, account-access rules, and contribution limits separately. The employer-match tool is also a simplified one-tier formula.

Why do today’s dollars and future dollars differ?

Inflation changes purchasing power. Future-dollar results describe the modeled account or expense amount at a later date. Today-dollar results discount that amount using your inflation assumption.

Are my entries sent to an account service?

This calculator runs in your browser and does not connect to your bank, employer, or investment accounts. Avoid entering account numbers or other sensitive details.

Educational estimates only. Results are not personalized financial, investment, tax, or legal advice and do not guarantee retirement income. Read the methodology and disclaimer.

Planning tools maintained by RetirementPlanCalc. Report a calculation issue.