Estimate how much your Bitcoin could be worth when you retire.
Current BTC Price
Your Details
Retirement Goal
Set to 0 to turn goal tracking off.
Used to convert today's target into retirement-date dollars.
Growth Model
Results
Loading the current Bitcoin price…
Methodology
Monthly compounding
An annual growth rate is converted to its monthly equivalent by compounding, not by division: monthlyRate = (1 + annualRate)^(1/12) − 1. A 15% year is therefore about 1.17% a month, not 1.25%. The simulation steps one calendar month at a time from today to your retirement date.
When purchases happen
Each monthly contribution buys Bitcoin at that month's starting price. Real purchases land at whatever the price is on the day you buy; this assumption keeps the projection deterministic and is applied identically every month. No purchase is made on the retirement date itself.
Growth models
Manual growth applies the single annual rate you choose to every year.
Stock-to-Flow is used to derive growth rates only. For each year the model computes a stock-to-flow ratio from Bitcoin's supply and issuance, evaluates PlanB's regression on it, and takes the compound annual rate between that year and the year 4 years later — one full halving cycle, so a halving is averaged across the years around it instead of landing as a single spike. Those percentages are then applied to the real current Bitcoin price. The regression's own dollar figure — the “theoretical price” — is never used as a projected price and is never displayed anywhere in these results.
Price data
The current Bitcoin price comes from CoinGecko and is cached on the server for five minutes. If it cannot be fetched, the last known price is used and labeled as such, or you are asked to enter a price yourself. Block height comes from Blockstream; if that is unavailable, the height is extrapolated from a known block at Bitcoin's target block interval.
Retirement spending goal
The target monthly spending you enter is in today's dollars. It is inflated to each projected month by compounding the annual inflation rate you set, using the same monthly-compounding convention as the growth models. Goal coverage compares it with the income a 4% withdrawal of the projected portfolio would pay at that point (portfolio × 4% ÷ 12); the 6% and 8% tiers show their own coverage on the income cards. Reaching 100% means the conservative 4% withdrawal covers the target on the day you retire — it is not a guarantee the money lasts through retirement. The inflation rate accepts 0% to 20%; deflation is not modeled, so a negative rate is rejected rather than run backwards.
What is not modeled
Taxes, transaction and exchange fees, and any income or spending outside the monthly contribution you enter. Inflation is applied only to your target monthly spending; portfolio values, prices, and contributions are all nominal US dollars.
Disclaimer
- This calculator is for education and curiosity. It is not financial, investment, tax or legal advice, and nothing here is a recommendation to buy or sell anything.
- Every figure shown is a hypothetical projection produced by compounding assumptions you or a model supplied. None of it is a prediction, and no outcome shown here is promised or likely simply because it appears on this page.
- Past performance and model performance say nothing about the future. A model that fit history well can fail completely going forward.
- Bitcoin is highly volatile. It has repeatedly lost more than 70% of its value and taken years to recover, and it could go to zero. Steady annual growth of the kind this calculator compounds has never been how it actually moved.
- The Stock-to-Flow model is experimental and widely criticized. It assumes scarcity alone drives price and ignores demand, regulation, competition and liquidity; its published forecasts have already been wrong by large margins.
- Do your own research and speak to a qualified financial adviser before making any investment decision. Never invest more than you can afford to lose.