Barista FIRE Calculator
This Barista FIRE calculator helps you plan for a semi-retired lifestyle where part-time work supplements withdrawals from savings. It supports multiple methods so you can compare a straight safe-withdrawal-rate (SWR) target, an SWR target with buffer and emergency reserve, and an estimate of how long it will take to reach your target given current savings and contributions.
Use the tool to explore sensitivity to key assumptions: part-time income, withdrawal rate, expected returns, inflation, and how many years of spending you want held as a buffer. All outputs are estimates to aid planning and should be interpreted with caution.
Governance
Record b73d351307fd • Reviewed by Fidamen Standards Committee
SWR target plus an optional multi-year spending buffer and explicit emergency reserve to reduce sequence-of-returns risk or early shortfalls.
Inputs
Results
Total required portfolio (with buffer and emergency fund)
$550,000.00
Buffer capital (years of shortfall)
$40,000.00
Base SWR target
$500,000.00
| Output | Value | Unit |
|---|---|---|
| Total required portfolio (with buffer and emergency fund) | $550,000.00 | USD |
| Buffer capital (years of shortfall) | $40,000.00 | USD |
| Base SWR target | $500,000.00 | USD |
Visualization
Methodology
The calculator implements three complementary methods: a basic SWR approach, an SWR approach augmented with a multi-year buffer plus an explicit emergency reserve, and a time-to-target projection that approximates years-to-go using an assumed constant real return.
Numerical computations assume constant parameters over time (constant withdrawal rate, constant contributions, and constant expected returns). For projections that solve for time, an approximate real return (nominal minus inflation) is used. Edge cases (zero or negative real return) can invalidate closed-form time estimates; inspect the outputs and use conservative assumptions when needed.
We follow best-practice software and numerical validation principles and recommend validating results against alternate methods. For secure data handling and testing guidance, see standards and guidelines from NIST, ISO, IEEE, and OSHA referenced below.
Worked examples
Example 1: Desired spending $30,000, part-time income $10,000, SWR 4% → annual shortfall $20,000 → SWR target $500,000.
Example 2: Same inputs with a 2-year buffer and $10,000 emergency reserve → total required = $500,000 + (2 × $20,000) + $10,000 = $550,000.
F.A.Q.
Is this financial advice?
No. This calculator provides estimates to support planning. It is not a substitute for professional financial advice. Consider discussing results with a licensed financial advisor or tax professional.
What is a safe withdrawal rate (SWR)?
SWR is an assumed sustainable percentage of a portfolio that can be withdrawn annually without depleting capital over a given horizon. Common rules of thumb (e.g., 4%) are simplifications and may not fit all situations; adjust for your risk tolerance and expected investment mix.
How accurate are the time-to-target projections?
Projections assume constant real returns and contributions. They are approximate; actual market volatility, taxes, fees, sequence-of-returns risk, and changes to contributions materially affect outcomes. When the approximate real return is near zero or negative, time-to-target formulas may be invalid or produce large errors.
Does the tool consider taxes and Social Security?
No. This calculator uses pre-tax nominal inputs for earnings and portfolio returns. Users should separately account for taxes, benefits, and other income sources.
How should I treat negative shortfall values?
If expected part-time income equals or exceeds desired spending, the computed shortfall may be zero or negative. Practically, treat negative shortfall as zero for the purpose of calculating needed portfolio capital, or adjust your desired spending assumptions.
What safeguards are in place for numerical reliability?
The tool uses double-precision arithmetic for internal math. It flags scenarios where denominators approach zero (for example, r ≈ 0 in time calculations) and recommends scenario analysis. For development and QA we recommend following IEEE floating-point guidance, numeric validation best practices, and input-range checks.
Sources & citations
- National Institute of Standards and Technology (NIST) — https://www.nist.gov
- International Organization for Standardization (ISO) — https://www.iso.org
- Institute of Electrical and Electronics Engineers (IEEE) — https://www.ieee.org
- Occupational Safety and Health Administration (OSHA) — https://www.osha.gov
- IRS Publication 590-B — Distributions from Individual Retirement Arrangements — https://www.irs.gov/publications/p590b
- IRS Required Minimum Distribution Worksheets — https://www.irs.gov/retirement-plans/plan-participant-employee/required-minimum-distribution-worksheets
- Social Security Administration — Retirement Benefits — https://www.ssa.gov/benefits/retirement/
Further resources
Related tools
Versioning & Change Control
Audit record (versions, QA runs, reviewer sign-off, and evidence).
Record ID: b73d351307fdWhat changed (latest)
v1.0.0 • 2025-11-29 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Public QA status
PASS — golden 25 + edge 120
Last run: 2026-01-23 • Run: golden-edge-2026-01-23
Versioning & Change Control
Audit record (versions, QA runs, reviewer sign-off, and evidence).
What changed (latest)
v1.0.0 • 2025-11-29 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Public QA status
PASS — golden 25 + edge 120
Last run: 2026-01-23 • Run: golden-edge-2026-01-23
Engine
v1.0.0
Data
Baseline (no external datasets)
Content
v1.0.0
UI
v1.0.0
Governance
Last updated: Nov 29, 2025
Reviewed by: Fidamen Standards Committee (Review board)
Credentials: Internal QA
Risk level: low
Reviewer profile (entity)
Fidamen Standards Committee
Review board
Internal QA
Entity ID: https://fidamen.com/reviewers/fidamen-standards-committee#person
Semantic versioning
- MAJOR: Calculation outputs can change for the same inputs (formula, rounding policy, assumptions).
- MINOR: New features or fields that do not change existing outputs for the same inputs.
- PATCH: Bug fixes, copy edits, or accessibility changes that do not change intended outputs except for previously incorrect cases.
Review protocol
- Verify formulas and unit definitions against primary standards or datasets.
- Run golden-case regression suite and edge-case suite.
- Record reviewer sign-off with credentials and scope.
- Document assumptions, limitations, and jurisdiction applicability.
Assumptions & limitations
- Uses exact unit definitions from the Fidamen conversion library.
- Internal calculations use double precision; display rounding follows the unit's configured decimal places.
- Not a substitute for calibrated instruments in regulated contexts.
- Jurisdiction-specific rules may require official guidance.
Change log
v1.0.0 • 2025-11-29 • MINOR
Initial publication and governance baseline.
Why: Published with reviewed formulas, unit definitions, and UX controls.
Areas: engine, content, ui • Reviewer: Fidamen Standards Committee • Entry ID: 72fc0b55d3a2