sborxyz/sbor

**Every lending venue in Bitcoin DeFi quotes its own rate. SBOR publishes the
market rate, read from contract state on Ethereum, Base, Arc, Arbitrum, BNB Chain and Stacks.**
A single venue's number cannot tell anyone, human or agent, whether the rate
they are offered is fair. SBOR, the Stacks Bitcoin Offered Rate, is a benchmark
for exactly that. On Stacks, where it started, it publishes one borrow
and one supply rate per currency: the SBOR indices. Beyond Stacks, it publishes
what it costs to borrow dollars against bitcoin: from the fixing of 14 October
2026 (methodology 1.13.0), the SBOR headline, BTC-COLLATERAL-USD, across every
dollar stablecoin lent against plain bitcoin, with a rate per stablecoin; before
that date, BTC-COLLATERAL-USDC, from Morpho on Base, Ethereum and Arc. All of it is read from contract state and published daily, beside
the largest lending markets on Ethereum, Base, Solana and Hyperliquid for
comparison. Free, no key, no rate limit, open to any agent on any chain.
Live at **sbor.xyz**
Stacks is a Bitcoin layer where smart contracts written in Clarity settle to
Bitcoin. It is where sBTC, a bitcoin-backed asset, and USDCx, Circle's native
USDC, are lent and borrowed.
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What it is
Every lending market on Stacks prices money differently, so comparing them
means opening each application by hand.
SBOR publishes one borrow rate and one supply rate per currency, weighted by
market depth and read directly from lending contract state rather than from any
venue's published figure. Each day's rates are also posted on-chain, on Arc,
Base, Hyperliquid, Solana and Stacks.
The model is SOFR, not a yield aggregator. SBOR does not route capital, hold
deposits, or recommend anything. It publishes a statistic.
Use it as a yardstick. Borrowing above SBOR means paying more than the market.
Supplying below it means earning less.
Indices
| Index | Covers |
|---|---|
| SBOR-USD | dollar markets, USDCx and USDh |
| SBOR-BTC | sBTC markets |
| SBOR-STX | STX and stSTX markets |
Published beside them, never inside them: a Proof of Transfer staking
reference, and the same asset classes on the largest lending markets on
Ethereum, Base, Hyperliquid and Solana, for comparison.
Beyond Stacks: borrowing dollars against bitcoin
From the fixing of 14 October 2026, methodology 1.13.0
(notice) makes BTC-COLLATERAL-USD the SBOR headline:
every market lending a dollar stablecoin against plain 1:1 bitcoin, priced by
its own interest rate model, on Morpho, Lista and Granite, across Ethereum,
Base, Arc, Arbitrum, BNB Chain and Stacks. A rate per stablecoin is published
once $25M or more of it carries weight. New markets phase in over 30 days.
From that fixing, latest.json carries bitcoinCollateralUsd: borrow, supply,
nominalBorrow, utilization, depthUsd (every market in full), weightedDepthUsd
(what carries weight that day), constituents, venues, chains,
largestConstituentWeight, subRates keyed by code (for example
BTC-COLLATERAL-RLUSD), and every market with its venue, chain, collateral,
loan, flags, phaseIn and weight. A rate that is withheld has no borrow and
carries withheld with the reason. bitcoinCollateralUsdc keeps its shape.
History rows carry btcCollateralUsd (b, s, u, d, wd, sub, markets) beside
btcUsdc. On-chain, BTC-COLLATERAL-USD is posted beside
BTC-COLLATERAL-USDC on all five chains; the other rates per stablecoin are in
the API. The MCP tools accept every code.
Before that date:
From the fixing of 25 September 2026, each fixing also carries
bitcoinCollateralUsdc: what it costs to borrow USDC against bitcoin, read from
the Morpho Blue markets on Base, Ethereum and Arc whose only collateral is
cbBTC, WBTC or cirBTC. Each market is published with its rate, utilization and depth, and a
reference weighted by depth when every market was read. It is a reference, not
an SBOR index, and never enters a fixing.
Data
No key, no registration, no rate limit, no fee. CORS open.