expiresAt. Fees explains the cost breakdown.
Estimate, quote, fixed delivery
GET /estimate is stateless and allocates no deposit address. It needs no key unless you pass affiliate fields. Use it as inputs change.
POST /quote requires a key, persists the quote, and returns deposit instructions. Its pricing lasts 2 minutes, subject to slippage.
deliveryMode: "fixed" commits to estimatedOut with timely, full funding. Finalized underpayment can reduce the target; overpayment does not increase it.
For /quote and /estimate, fixed delivery requires exact-in, destination membership in fixedTo, and partner support. Unsupported requests fail; onramp can fall back for some availability failures, but still rejects unsupported routes. Trust the returned deliveryMode.
Both endpoints use route-dependent slippageBps defaults and minimums. Omit it to use the route’s default.
Fund before expiresAt. Eligible late funding uses refreshed market pricing without the original price or fixed-output guarantee. Some expired submissions are rejected.
Amounts
Amounts are integer strings in smallest units:"50000000" is 50 Base USDC; "100000" is 0.001 BTC. Read each asset’s decimals from /routes.
exact_in(default):amountis source units. ReadamountInandestimatedOut.exact_out:amountis destination units. ReadtargetAmountOut,requiredAmountIn,maxAcceptedAmountIn, andinputBufferBps. The destination must be inexactOutTo. Stablecoin targets must be whole cents, such as multiples of10000for a 6-decimal asset.
amountFiatUsd instead of amount. Eligible stablecoin onramps can select fiat-capped exact-out when partner fees are invoiced and no app or affiliate fees apply. Explicit exact_in prevents that selection. Use the returned mode and amounts.
/quote requires refundAddress for exact-out and Lightning destinations. Onramp leaves it optional, but missing refund details can obstruct recovery. Supply a valid refund target wherever supported.
Lightning destinations take a BOLT11 invoice as recipientAddress: amountless for exact-in; amountless or matching the target for exact-out.
Send the returned amountIn. Accepted differences can update input, fees, and output; route minimums, maximums, and funding rules still apply. Dust may create no order, and over-limit funding can be held. Lightning source invoices fix the amount.