Get a quote

A quote answers one question: if my customer sends this much, how much do they get? Every payment starts with a quote.

What you send

Field	What it means	Example
`customer_id`	The customer this quote is for	`cus_4hT9…`
`transaction_type`	`onramp` (fiat → stablecoin) or `offramp` (stablecoin → fiat)	`onramp`
`source_amount`	How much your customer sends, as text	`"150000"`
`source_currency`	What your customer sends	`NGN`
`target_currency`	What your customer receives	`USDC`
`network`	The blockchain for the stablecoin	`solana`
`payment_method`	Onramp only. How your customer pays the fiat	`bank_transfer`
`payout_method`	Offramp only. How your customer receives the fiat	`momo`

Send only one of payment_method or payout_method. An onramp uses payment_method, an offramp uses payout_method. The stablecoin side is filled in for you. If you leave out payout_method on an offramp, we use bank_transfer.

Onramp quote

curl -X POST https://sandbox.core.linkio.world/api/quotes/generate \
  -H "X-BRIDGE-API-Key: $BRIDGE_API_KEY" \
  -H "API-Version: 2026-10-29-atlas" \
  -H "Content-Type: application/json" \
  -d '{
    "customer_id": "cus_4hT9pL2mQx8VnR3tY7wZ1cB5dE",
    "transaction_type": "onramp",
    "source_amount": "150000",
    "source_currency": "NGN",
    "target_currency": "USDC",
    "payment_method": "bank_transfer",
    "network": "solana"
  }'

Offramp quote

curl -X POST https://sandbox.core.linkio.world/api/quotes/generate \
  -H "X-BRIDGE-API-Key: $BRIDGE_API_KEY" \
  -H "API-Version: 2026-10-29-atlas" \
  -H "Content-Type: application/json" \
  -d '{
    "customer_id": "cus_4hT9pL2mQx8VnR3tY7wZ1cB5dE",
    "transaction_type": "offramp",
    "source_amount": "100",
    "source_currency": "USDC",
    "target_currency": "GHS",
    "payout_method": "momo",
    "network": "base"
  }'

What you get back

201 Created:

{
  "status": "success",
  "message": "Quote generated",
  "quote": {
    "id": "qte_9xLp3VnR7tY1wZ4cB6dE8fK2mQ",
    "source_amount": "150000",
    "source_currency": "NGN",
    "target_amount": "97.71",
    "target_currency": "USDC",
    "payment_method": "bank_transfer",
    "payout_method": "stablecoin",
    "network": "base",
    "transaction_type": "onramp",
    "rate": "1535",
    "expires_at": "2026-10-28T10:15:20.000Z"
  }
}

Field	What it means
`id`	The quote ID. Use it to create the payment.
`target_amount`	How much your customer receives.
`rate`	How many units of fiat equal 1 stablecoin.
`expires_at`	When the price stops being valid.
`processor_fee`, `vat`, `amount_expected`	Sometimes included. When present, `amount_expected` is the exact total your customer must send.

Quotes last about 20 seconds. Show the price to your customer, and create the payment as soon as they confirm. See Time limits.

Refresh an expired quote

Refresh the quote before you create the payment if either of these is true:

The quote has expired (the time in expires_at has passed).
More than 10 seconds have passed since you got the quote.

Refreshing keeps the same quote ID. You get a new price and a new expires_at, so check the new price with your customer if it has changed.

curl https://sandbox.core.linkio.world/api/quotes/qte_9xLp3VnR7tY1wZ4cB6dE8fK2mQ/refresh \
  -H "X-BRIDGE-API-Key: $BRIDGE_API_KEY" \
  -H "API-Version: 2026-10-29-atlas"

The response looks the same as above, with "message": "Quote refreshed".

What can go wrong

Status	Code	Why	What to do
`422`	`validation_failed`	A field is wrong. For example, a currency isn’t supported, both currencies are the same, `payment_method` was sent on an offramp, or the amount has too many decimal places.	Read `errors`, fix the field.
`422`	`invalid_amount`	The amount is below the minimum or above the maximum.	See Limits.
`403`	`pair_not_enabled`	The currency pair isn’t turned on for your business.	See Currency pairs.
`404`	`customer_not_found`	The customer ID doesn’t exist for your business.	Check the ID.
`409`	`customer_banned`	The customer is banned.	Contact support.
`404`	`quote_not_found`	(Refresh) The quote ID doesn’t exist, or it was deleted.	Get a new quote.
`409`	`quote_locked`	(Refresh) The quote is used by a payment that has already received the money.	The price is final; nothing to do.
`503`	`route_temporarily_unavailable`	We currently don’t support this corridor or its in the works.	Try again in a moment or contact support.
`504`	`request_timeout`	A quote request took too long to process.	Try again.

Example of an unsupported method:

{
  "error": {
    "type": "validation_error",
    "code": "validation_failed",
    "message": "Request validation failed",
    "request_id": "req_3VnR7tY1wZ4cB6dE8fK2mQ9xLp",
    "status": 422,
    "errors": [
      {
        "field": "payment_method",
        "message": "payment_method momo is not supported for NGN onramp. Allowed: bank_transfer"
      }
    ]
  }
}

Create an onramp or an offramp with this quote.

Get started

Set up your account

Before you build

Core flows

Webhooks

Errors

What you send

Onramp quote

Offramp quote

What you get back

Refresh an expired quote

What can go wrong

Next

​What you send

​Onramp quote

​Offramp quote

​What you get back

​Refresh an expired quote

​What can go wrong

​Next

What you send

Onramp quote

Offramp quote

What you get back

Refresh an expired quote

What can go wrong

Next