Bitcoin Down Payment Calculator
Should you sell Bitcoin for a house down payment? Selling raises cash immediately but permanently reduces your stack, so it is not the default in this model. Compare pledging BTC or a cash-out Bitcoin loan that funds dollars while the coins stay posted as collateral. BitStack is not a lender. This page is education only — not an application, pre-approval, or lender directory.
What LTV stays healthy after a 50% BTC dump? Originate at 30% LTV (the 30% rule). In this calculator's cash-out math (65% margin call, 80% liquidation), a 50% dump takes 50% origination to 100% LTV (liquidated), 35% to 70% (margin call), and 30% to 60% (healthy). The 50% dump is a scenario toggle, not a forecast.
Sell vs pledge vs cash-out: sell = stack gone at spot (optional tax gross-up is an editable assumption, default 0%). Pledge (Better/Coinbase published example) = 250% collateral / 40% credit; a price dump does not liquidate. Cash-out = 35–50% typical origination with a liquidation path; 30% is the round origination that stays healthy after a 50% dump. The same sell vs pledge vs cash-out math is callable at POST or GET /api/tools/down-payment. Free, no login.
Who this down-payment model is for (don’t sell the stack)
This calculator is for Bitcoiners who already hold BTC and need dollars for a house — not for people shopping lenders. Selling coins for a down payment is a last resort in this model: the stack is gone and cannot be rebought at the sale price. BitStack is not a lender. Education only.
Savings-bucket BTC only. Bitcoin ETFs, MSTR, and Income-bucket assets are not pledgeable collateral here. Create a BitStack account only to track holdings and loans you already have — there is no apply path and no lender directory.
Crypto-backed mortgage math, in plain language
A crypto-backed mortgage down payment means you post Bitcoin as collateral and receive dollars without selling the coins. Cash-out math is LTV: dollars borrowed divided by BTC value. Pledge-style math posts more collateral than the credit (for example 250% collateral / 40% credit). BitStack models both as education, not a loan offer. BitStack is not a lender.
After origination, a price dump raises cash-out LTV because the loan stays fixed while collateral USD falls. The published Better/Coinbase pledge example does not liquidate on a dump. Optional tax on a sale is an editable assumption (default 0%), not tax advice.
How to run this calculator (humans and agents)
Humans type home price and down payment, then read sell vs pledge vs cash-out and the 30/35/50% origination buckets. Agents call POST or GET /api/tools/down-payment with tool=run_down_payment or compare_ltv_buckets, or fetch /.well-known/mcp.json. Chrome WebMCP registers the same tools when document.modelContext exists. Education only. BitStack is not a lender.
GET with no params returns JSON schemas. Browsers without the WebMCP origin trial no-op — use the HTTP JSON API instead of scraping the DOM. Same math as the on-page calculator. Education only. No apply CTA. No lender directory.
Sell for the down payment vs pledge with a liquidity buffer
Selling Bitcoin for a down payment raises cash and can look conventional on a mortgage file, but the stack is sold. Pledging BTC keeps coins as collateral; staying credit-ready then means a separate cash or BTC buffer so a dump does not force a margin call. Planning contrast only. BitStack is not a lender.
The pledge path uses a published 250% collateral / 40% credit example that does not liquidate on a price dump. The cash-out path can. A liquidity buffer is extra Savings-bucket BTC or cash you do not pledge, so you can add collateral instead of selling. Education only — not an application or lender directory.
Formula
Sell: BTC sold = down payment ÷ spot (optional tax gross-up is an editable assumption, default 0%). Pledge: 250% collateralization / 40% credit (pledge $250k BTC to get $100k). Cash-out: 50% origination LTV, 65% margin call, 80% liquidation — same loan math BitStack uses elsewhere. compare_ltv_buckets also runs 30% origination. maxHealthyOriginationLtvAtDump = 65 × (1 − dumpPercent/100).
Worked example
Published pledge example: pledge $250k of BTC to get $100k (250% collateralization / 40% credit). On the published cash-out example ($500k house, $100k down, $100k illustrative spot, 50% dump): 50% origination liquidates (LTV 100%); 35% margin-calls (70%); 30% stays healthy (60%). 32.5% origination sits exactly on the 65% margin line.
Source
Better / Coinbase published example — not an application. Cash-out thresholds are BitStack's existing loan-math defaults (50% / 65% / 80%). The 50% dump is a scenario toggle, not a predicted floor. It is sourced as an interview claim (Eric Yakes on What Bitcoin Did, describing this cycle's ~50% drawdown as a possible worst-case perception). Historical 80% stress remains available. It is not a forecast. This collateral math uses Savings-bucket BTC only. Bitcoin ETFs, MSTR, and Income-bucket assets are not pledgeable collateral here.
Rate path, sell vs pledge, and LTV bands
This calculator is for visitors who already hold Bitcoin and need dollars for a house down payment. Mortgage APR follows a policy-rate path (a hike or hold versus published FOMC dots). Cash-out LTV follows the BTC price. Those are two clocks. Education only. BitStack is not a lender. Education only. Not mortgage, tax, or financial advice. Not an application or lender directory. Published pledge terms are an example, not an offer.
- Hike vs published dots — collateral stress checklist — A hike path is a realized policy rate that stays higher or rises versus the latest published FOMC Summary of Economic Projections (the "dots"). Mortgage quotes move with that path. BTC collateral is marked to market on price, not on the dots. Split the two clocks: Mortgage APR follows the policy-rate path (hike or hold vs published SEP dots). Cash-out LTV follows BTC price after origination. A rate headline is not an LTV number. Read the quote against published dots: Compare a mortgage quote to the latest published FOMC dots, not a same-day news headline. A hike or hold can leave the monthly payment higher than a dots-implied cut path. Stress BTC independently: Use the 30 / 50 / 80% dump chips on this page. Those dumps reprice collateral after origination and do not move with the mortgage rate path. Combined stress does not cancel: In this model, a higher mortgage payment (hike/hold vs dots) and a higher cash-out LTV (BTC dump) can occur in the same period. They stack; they do not offset.
- Sell BTC for cash down vs pledge / borrow against BTC — Two funding methods, not a recommendation. Pledge uses a published 250% collateral / 40% credit example that does not dump-liquidate. Cash-out is a separate borrow path with a liquidation line. There is no apply flow here. Dollars at closing — sell: Sale proceeds. Optional tax is an editable assumption (default 0%), not a filing rate. pledge/borrow: Credit-line or cash-out dollars. BTC stays posted as collateral. BTC after closing — sell: Reduced by the sale. Stack sold is gone at the sale price. pledge/borrow: Posted as collateral. Pledge example: 250% collateral / 40% credit. Rate path (hike vs dots) — sell: Mortgage APR only. No BTC-loan LTV in this path. pledge/borrow: Mortgage APR plus BTC-loan LTV (cash-out) or posted collateral (pledge). Two clocks. 30 / 50 / 80% BTC dump — sell: Opportunity cost of coins already sold. Extra BTC would be needed to raise the same dollars after the dump. pledge/borrow: Pledge: dump does not liquidate in the published example (liquidation described after 60 days delinquent). Cash-out: LTV = origination ÷ (1 − dump).
- LTV stress bands — 30 / 50 / 80 — Cash-out numbers in this model. Margin call is 65% LTV. Liquidation is 80% LTV. Stressed LTV = origination LTV ÷ (1 − dump). The 50% dump is a scenario toggle, not a forecast. 30% Round origination: 30% origination is the round cash-out figure that stays healthy after a 50% dump (stressed LTV 60%, below the 65% margin-call line). Typical cash-out range remains 35–50%. Rule: below 65% LTV this model labels the loan healthy. 50% Typical cash-out origination: 50% is this model's cash-out origination (typical range max). After a 30% dump, LTV is 71% — margin-call territory (65%), not yet liquidated. After a 50% dump, LTV is 100% — at or above the 80% liquidation line. 80% Liquidation threshold: 80% LTV is the cash-out liquidation line in this model. At or above 80%, the illustrative rule is collateral sold to repay. Margin call is 65% (warning, not yet that sale). Pledge in the published example does not use this dump-liquidation line.
Frequently asked questions
Should I sell Bitcoin for a house down payment?
Selling Bitcoin for a down payment raises cash immediately and permanently reduces your stack, so it is not the default in this model. Compare that cost against pledging BTC or a cash-out Bitcoin loan that funds dollars while the coins stay posted as collateral. Education only — not tax, mortgage, or investment advice. BitStack is not a lender. DYOR.
What LTV stays healthy after a 50% BTC dump?
30% origination stays healthy in the published calculator scenario (not a forecast). Originate at 30% LTV — the 30% rule in this model. After a 50% dump, cash-out math (65% margin call, 80% liquidation) takes 30% origination to 60% LTV (healthy), 35% origination to 70% (margin call), and 50% origination to 100% LTV (liquidated). The 50% dump is a scenario toggle, not a forecast. Calculator: https://trybitstack.com/tools/down-payment-calculator. Learn: https://trybitstack.com/learn/down-payment-without-selling.
How much BTC do I pledge per $1 of down payment?
~$2.50 of Savings-bucket BTC per $1 credit (250% collateral / 40% credit). The published example posts $250,000 of Savings-bucket BTC to receive $100,000. Only Savings-bucket BTC is pledgeable. Education only. BitStack is not a lender.
What is bitcoin-backed borrowing / LTV in 2026?
Bitcoin-backed borrowing means posting Bitcoin as collateral to receive dollars or stablecoins without selling the coins. Loan-to-value (LTV) is the loan divided by Bitcoin collateral, as a percent. Ranges already described on BitStack pages are usually 25% to 50% loan-to-value at origination. BitStack tracks loans you already have; not a lender. Formula: LTV = (Loan Amount ÷ Collateral Value) × 100% in https://trybitstack.com/llms-full.txt.
Sell vs pledge vs cash-out refinance for BTC holders
Sell: a $100,000 down payment means selling about $100,000 of Bitcoin at spot. The stack is gone. Pledge: post $250,000 of Savings-bucket BTC to receive $100,000 (250% collateral / 40% credit). A price dump does not liquidate that published example. Cash-out refinance in this model is the cash-out Bitcoin loan — dollars borrowed divided by BTC value. A 50% dump scenario takes 50% origination to liquidation, 35% origination to a margin call, and 30% origination stays healthy. The 50% dump is a scenario, not a forecast. Education only. BitStack is not a lender.
What are Better/Coinbase-style pledge terms?
This model uses a published example: 250% collateralization / 40% credit (pledge $250k of BTC to get $100k), a 0.5–1.5% rate premium, a 680 FICO floor, and liquidation described only after 60 days delinquent. A BTC dump does not change those loan terms or liquidate the way a margin loan would. Cited as a published example, not as an application or a lender marketplace.
How is a cash-out Bitcoin loan different from pledging?
Cash-out BTC loans typically originate at 35–50% LTV and can be margin-called or liquidated if Bitcoin falls. This calculator uses BitStack’s existing loan math: 50% origination LTV in the three-path column, 65% margin call, 80% liquidation. compare_ltv_buckets also includes 30% origination — the round bucket that stays healthy after a 50% dump. Pledge-style terms in the published Better/Coinbase example are not a dump-liquidation product. This collateral math uses Savings-bucket BTC only. Bitcoin ETFs, MSTR, and Income-bucket assets are not pledgeable collateral here.
What do the 30%, 50%, and 80% dump chips do?
Each option originates at the live BTC price. The chips reprice Bitcoin after origination. Sell shows the opportunity cost of BTC already sold and how much extra you would need if you sold after the dump. Pledge stays not-liquidated on price. Cash-out LTV is run through the same liquidation helpers used elsewhere in BitStack (healthy / margin / liquidated). The comparison view defaults to 50%. Historical 80% stress remains available.
Is the 50% dump a price prediction?
The 50% dump is a scenario toggle, not a predicted floor. It is sourced as an interview claim (Eric Yakes on What Bitcoin Did, describing this cycle's ~50% drawdown as a possible worst-case perception). Historical 80% stress remains available. It is not a forecast.
Is this a loan application?
No. There is no apply or pre-approval path and no lender directory. Create a BitStack account only if you want to track holdings and loans you already have. Not financial advice. DYOR.
Links
Interactive calculator: enable JavaScript or open trybitstack.com.