Quickstart

This guide gets you to a working API call fast. You’ll need a sandbox API key — create one in seconds under Account → Manage Accounts in the sandbox dashboard (no approval needed). New here? See Initial Setup for full account setup, base URLs, and going to production.

Make your first call

Use the sandbox base URL https://api.sand.etherfuse.com and send your key in the Authorization header — with no Bearer prefix (see Authentication).A connectivity check is the simplest authenticated request:

curl https://api.sand.etherfuse.com/ramp \
  -H "Authorization: <your_sandbox_api_key>"

Or hit a public endpoint that needs no auth — list the available stablebonds:

curl https://api.sand.etherfuse.com/lookup/stablebonds

See what your customers can trade

Once authenticated, discover the assets available to ramp on a given chain. Use the identifier from the response when you create a quote.

curl "https://api.sand.etherfuse.com/ramp/assets?blockchain=solana" \
  -H "Authorization: <your_sandbox_api_key>"

See GET /ramp/assets.

Get a quote

Quotes return pricing (exchangeRate, feeBps, feeAmount, destinationAmount) and expire after 2 minutes. A quote needs an onboarded customerId, so complete onboarding first. The asset pair goes in quoteAssets (type is onramp, offramp, or swap).

curl -X POST https://api.sand.etherfuse.com/ramp/quote \
  -H "Authorization: <your_sandbox_api_key>" \
  -H "Content-Type: application/json" \
  -d '{
    "quoteId": "<uuid>",
    "customerId": "<onboarded_customer_uuid>",
    "blockchain": "solana",
    "sourceAmount": "1000",
    "quoteAssets": {
      "type": "onramp",
      "sourceAsset": "MXN",
      "targetAsset": "<token_identifier>"
    }
  }'

See POST /ramp/quote for the full payload, and the path-specific guides below for complete examples.

Pick your path

Onramp

Fiat → tokens. The customer deposits MXN and receives tokens.

Offramp

Tokens → fiat. The customer sends tokens and receives MXN.

Swap

Token → token. The customer exchanges one asset for another.

Next steps

Onboard customers

Most flows require a KYC’d customer with a linked bank account first.

Monitor with webhooks

Get real-time, HMAC-signed updates instead of polling.

Understand the model

Quote types, fees, order status flows, and resources.

Sandbox reference

Test KYC data, sandbox RFCs, and testnet token details.

Introduction Initial Setup

⌘I

Get Started

Concepts

User Authentication

Integration Guides

Blockchains

Resources

Pick your path

Onramp

Offramp

Swap

Next steps

Onboard customers

Monitor with webhooks

Understand the model

Sandbox reference

​Pick your path

Onramp

Offramp

Swap

​Next steps

Onboard customers

Monitor with webhooks

Understand the model

Sandbox reference

Pick your path

Next steps