Cross-chain Quotes & Routing

Before initiating a cross-chain transfer or creating an intent, you can request a quote from Chainrails. The quote engine provides comprehensive information about how a transaction will be executed — including the route, estimated fees, and destination amount. This allows your app to show users exactly what to expect before they fund the transaction.

Requesting Quotes

The quote engine provides comprehensive cross-chain transfer quotes from a single bridge, multiple bridges or even multiple source chains. You can retrieve:

Some quote endpoints take in an optional amountSymbol parameter which can be used to specify the denomination of the amount you want to send. For quotes in USD, you can either set amountSymbol to USDC (or leave it empty).You can quote in a different denomination than the token you want to send. For example, you can set amountSymbol to USDC, while sending ETH as tokenIn

A single quote for a specific route

cURL
JavaScript
PHP

curl --request GET \
  --url "https://api.chainrails.io/api/v1/quotes/single?tokenIn=0x036CbD53842c5426634e7929541eC2318f3dCF7e&tokenOut=0x75faf114eafb1BDbe2F0316DF893fd58CE46AA4d&sourceChain=BASE_TESTNET&destinationChain=ARBITRUM_TESTNET&amount=1000000&bridge=CCTP" \
  --header "Authorization: Bearer YOUR_API_KEY"

const fetch = require("node-fetch");

const url = new URL("https://api.chainrails.io/api/v1/quotes/single");

url.search = new URLSearchParams({
  tokenIn: "0x036CbD53842c5426634e7929541eC2318f3dCF7e",
  tokenOut: "0x75faf114eafb1BDbe2F0316DF893fd58CE46AA4d",
  sourceChain: "BASE_TESTNET",
  destinationChain: "ARBITRUM_TESTNET",
  amount: "1000000",
  bridge: "CCTP",
}).toString();

(async () => {
  const res = await fetch(url, {
    method: "GET",
    headers: {
      Authorization: `Bearer YOUR_API_KEY`,
    },
  });

  const data = await res.json();
  console.log("Quote:", data);
})();

<?php

$apiKey = "YOUR_API_KEY";
$baseUrl = "https://api.chainrails.io/api/v1/quotes/single";

$params = http_build_query([
  "tokenIn" => "0x036CbD53842c5426634e7929541eC2318f3dCF7e",
  "tokenOut" => "0x75faf114eafb1BDbe2F0316DF893fd58CE46AA4d",
  "sourceChain" => "BASE_TESTNET",
  "destinationChain" => "ARBITRUM_TESTNET",
  "amount" => "1000000",
  "bridge" => "CCTP",
]);

$url = "$baseUrl?$params";

$ch = curl_init($url);
curl_setopt_array($ch, [
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer $apiKey"
  ],
]);

$response = curl_exec($ch);

if (curl_errno($ch)) {
  echo 'Error: ' . curl_error($ch);
} else {
  echo "Response: " . $response;
}

curl_close($ch);

Or a multi-source quote for a given destination chain

Useful for when you want to show users all source options and their respective fees to send funds to a specific destination chain.

cURL
JavaScript
PHP

curl --request GET \
  --url "https://api.chainrails.io/api/v1/quotes/multi-source?destinationChain=ARBITRUM_TESTNET&amount=1.5&tokenOut=0x75faf114eafb1BDbe2F0316DF893fd58CE46AA4d" \
  --header "Authorization: Bearer YOUR_API_KEY"

const fetch = require("node-fetch");

const url = new URL("https://api.chainrails.xyz/api/v1/quotes/multi-source");

url.search = new URLSearchParams({
  destinationChain: "ARBITRUM_TESTNET",
  amount: "1.5",
  tokenOut: "0x75faf114eafb1BDbe2F0316DF893fd58CE46AA4d",
}).toString();

(async () => {
  const res = await fetch(url, {
    method: "GET",
    headers: {
      Authorization: `Bearer YOUR_API_KEY`,
    },
  });

  const data = await res.json();
  console.log("Quotes from multiple sources:", data);
})();

<?php

$apiKey = "YOUR_API_KEY";
$baseUrl = "https://api.chainrails.io/api/v1/quotes/multi-source";

$params = http_build_query([
  "destinationChain" => "ARBITRUM_TESTNET",
  "amount" => "1.5",
  "tokenOut" => "0x75faf114eafb1BDbe2F0316DF893fd58CE46AA4d",
]);

$url = "$baseUrl?$params";

$ch = curl_init($url);
curl_setopt_array($ch, [
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer $apiKey"
  ],
]);

$response = curl_exec($ch);

if (curl_errno($ch)) {
  echo 'Error: ' . curl_error($ch);
} else {
  echo "Response: " . $response;
}

curl_close($ch);

You can also get quotes from multiple bridges for a specific route, filter for best quotes and more. See the API reference for all available quote endpoints.

For most cases, you would want to use the multi-source quoting as it shows the user all the best quotes to choose from.

The Routing Engine

The Routing Engine provides extensive details about supported bridges, their available routes, and the optimal route for a given transfer intent. For most use cases, the quote engine is sufficient but if you want more fine grained control over bridge selection, you can use the routing engine directly. You can consult the API reference for all available routing endpoints.

Parameters Reference

Parameter	Type	Required	Description	Example
tokenIn	`string`	✅ Yes (for `/quotes/single`)	Address of the input token on the source chain. This is the token the user will send.	`0x036CbD53842c5426634e7929541eC2318f3dCF7e`
tokenOut	`string`	✅ Yes	Address of the output token on the destination chain.	`0x06ef8BFf21a47c8E15944D1f4A68F9F95f66A34`
sourceChain	`string`	✅ Yes (for `/quotes/single`)	The blockchain where the user is sending funds from. Must be one of the supported chain identifiers.	`BASE_TESTNET`
destinationChain	`string`	✅ Yes	The blockchain where the funds should arrive. Must be one of the supported chain identifiers.	`ARBITRUM_TESTNET`
amount	`string`	✅ Yes	Amount to transfer, in token units. Supports decimals.	`"1.5"`
bridge	`string`	✅ Yes (for `/quotes/single`)	The specific bridge protocol to use for the quote.	`ACROSS`
recipient	`string`	❌ Optional	Address of the final recipient of the transfer.	`0xb79541Be080a59fdcE6C0b43219ba56c725eC65e`

Introduction

Concepts

Developer Guides

Essentials

Requesting Quotes

A single quote for a specific route

Or a multi-source quote for a given destination chain

The Routing Engine

Parameters Reference

​Requesting Quotes

​A single quote for a specific route

​Or a multi-source quote for a given destination chain

​The Routing Engine

​Parameters Reference

Requesting Quotes

A single quote for a specific route

Or a multi-source quote for a given destination chain

The Routing Engine

Parameters Reference