Merkle tree root & proofs API

Build a Merkle root, generate a proof for a leaf, or verify a proof — using the keccak256 + sorted-pairs convention that Solidity's OpenZeppelin MerkleProof verifier expects, so proofs verify on-chain. For airdrops and allowlists. Answers 'merkle root for these addresses', 'generate a merkle proof', 'verify this proof'.

Price$0.01per request

MethodPOST

Route/v1/chain/merkle

StatusLive

MIME typeapplication/json

Rate limit60/minute

CacheNo cache

chainmerkleairdropallowlistproofkeccak256openzeppelin

API URLhttps://x402.hexl.dev/v1/chain/merkle

Integration docs

Example request

{
  "op": "root",
  "leaves": [
    "0x1111111111111111111111111111111111111111",
    "0x2222222222222222222222222222222222222222"
  ]
}

Example response

{
  "op": "root",
  "root": "0x...",
  "leafCount": 2
}

Input schema

{
  "type": "object",
  "required": [
    "op"
  ],
  "properties": {
    "op": {
      "type": "string",
      "enum": [
        "root",
        "proof",
        "verify"
      ]
    },
    "leaves": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "description": "leaf values (e.g. addresses)"
    },
    "leaf": {
      "type": "string"
    },
    "proof": {
      "type": "array",
      "items": {
        "type": "string"
      }
    },
    "root": {
      "type": "string"
    }
  }
}

Output schema

{
  "type": "object",
  "additionalProperties": true
}