US FIRE (Financial Independence, Retire Early) Calculator

Estimate the savings required for Financial Independence (FIRE) in the U.S., and project how long to reach it given your current savings, contributions, and expected return. Includes tax-adjusted guidance and references.

Page updated:: Jan 3, 2026
Tool version:: v1.1.0

Overview

This calculator estimates the portfolio size required to pursue Financial Independence (FIRE) in the U.S., then projects how long it will take to reach that target given your current savings, annual contributions, expected real return, withdrawal rate, and tax assumptions.

Use the inputs to model different withdrawal and tax scenarios. Results are estimates — see methodology and citations for details.

Current savings (principal)

Your current invested savings for retirement/FIRE. · Min 0 · Max 100000000

Estimated annual spending in retirement (after inflation)

How much you expect to spend per year in today's dollars. · Min 0 · Max 5000000

Safe withdrawal rate (decimal)

Portion of portfolio withdrawn in year 1. Common baseline: 0.04 (4%). · Min 0.005 · Max 0.2

Effective tax rate on withdrawals (decimal)

Estimate of taxes applied to retirement withdrawals (federal + state). · Min 0 · Max 0.6

Annual pre-tax savings/contributions

Amount you plan to add to investments each year until FIRE. · Min 0 · Max 10000000

Expected real annual return (decimal)

Expected annual return after inflation (used for projection). · Min -0.1 · Max 0.2

Results

Target portfolio (pre-tax) using withdrawal rate

$1,000,000.00

Target portfolio required (tax-adjusted)

$1,176,470.59

Estimated years to reach FIRE

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Interpretation note

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How to read the result

What it means: The displayed value is an estimate based on your inputs. It represents the calculated scenario under current assumptions, not a guaranteed amount.
Next step: Use the result as a starting point. Adjust parameters to compare scenarios and validate with a professional when needed.
Calculation limits: The model uses simplified formulas and cannot account for all variables in your specific case (local regulations, personal conditions, temporal changes).

Methodology

Primary target calculation: target = annual_spending / withdrawal_rate. This is a standard FIRE heuristic (e.g., the 4% rule => 25x expenses).

Tax adjustment: required_savings = annual_spending / (withdrawal_rate * (1 - tax_rate)). This inflates the required portfolio to cover taxes on withdrawn amounts.

Projection to target: We solve the future-value equation for n (years) assuming constant real return and annual contributions: current*(1+r)^n + annual_savings*((1+r)^n -1)/r = required_savings. The calculator uses the closed-form rearrangement when r != 0; when r=0 it uses a linear projection.

All outputs are estimates. Adjust inputs for your expected tax treatment, future spending inflation, and sequence-of-returns risks.

Glossary+

Withdrawal rate: The portion of the portfolio withdrawn in the first year of retirement; used to derive a target portfolio as spending / withdrawal_rate.
Real return: Expected investment return after accounting for inflation.
Required savings (tax-adjusted): Target portfolio adjusted to cover taxes on withdrawals so after-tax spending equals your annual_spending input.

Key takeaways

This tool provides a transparent, parameterized estimate of FIRE targets and a projection for time-to-FIRE based on user inputs.

Review the assumptions (withdrawal rate, tax rate, return) and consult a qualified advisor for personalized planning.

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Useful links

Worked examples

Example — baseline

User has $10,000 current savings, expects $40,000 spending, uses 4% withdrawal rate, 15% tax on withdrawals, saves $10,000/year, expects 5% real return.

Interpretation

Under these assumptions the raw 4% target is $1,000,000; after adjusting for taxes it becomes ~$1.18M. At $10k/year contributions and 5% real return, that reaches in ~26 years.

Frequently asked questions

Why adjust for tax rate?

Withdrawals from taxable accounts and some retirement accounts are reduced by income tax. To maintain the same after-tax spending, the gross withdrawal must be larger; the calculator adjusts the target portfolio accordingly.

What is a safe withdrawal rate?

Common guidance uses 3–4% as a starting point; personal factors (sequence of returns, retirement length, health, tax strategy) affect the appropriate rate.

Can I use inflation adjustments?

This calculator uses real (inflation-adjusted) returns and assumes annual_spending is in today's dollars. To model inflation separately, adjust real_return and spending inputs accordingly.

Sources & references

Trinity Study (Bengen / SWR literature): https://www.trinity.edu
IRS - Internal Revenue Service (tax information): https://www.irs.gov
Vanguard: Portfolio construction and forecasting: https://www.vanguard.com

Quality & oversight

Author: Ugo Candido, MBA
Maintained by: Ugo Candido, MBA
Page updated: Jan 3, 2026
Tool version: v1.1.0

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