@0x/0x-parser

0x-parser

Blockchain Support

Arbitrum	Avalanche	Base	BNB Chain	Blast	Ethereum
Linea	Mantle	Optimism	Polygon	Scroll	Mode
Worldchain	Unichain	Berachain	🔜	🔜	🔜

Overview

This library is designed for 0x integrators, simplifying the complex task of parsing 0x transactions into a format that is both user-friendly and easy to understand. When swapping tokens, one of the challenges is that the trade can experience slippage through Automated Market Makers (AMMs). This makes the final swap amounts difficult to predict prior to executing the trade. However, this library overcomes that challenge by parsing the transaction receipt and event logs to accurately identify the final swap amounts.

Demo

Try out the parser in a live code environment directly in your browser 🌐. You can also experience it in action through the demo UI app, which is built with 0x-parser.

Requirements

0x-parser relies on the debug_traceTransaction Ethereum JSON-RPC method to parse 0x transactions. Ensure that your RPC node supports this method.

Installation

Step 1: Install Peer Dependency

First, make sure you have the required peer dependency viem installed. If you haven't installed it yet, you can do so with the following command:

npm install viem

Step 2: Install the Parsing Library

After installing the peer dependency, proceed to install the @0x/0x-parser package:

npm install @0x/0x-parser

Usage

import { parseSwap } from "@0x/0x-parser";
import { createPublicClient } from "viem";
import { http } from "viem";
import { mainnet } from "viem/chains";

async function main() {
  const RPC_URL = `https://eth-mainnet.g.alchemy.com/v2/${process.env.ALCHEMY_API_KEY}`;

  // You can pass any transaction hash that you got after submitted a 0x transaction:
  // https://etherscan.io/address/0x2fc205711fc933ef6e5bcc0bf6e6a9bfc220b2d8073aea4f41305882f485669d
  const transactionHash = `0x2fc205711fc933ef6e5bcc0bf6e6a9bfc220b2d8073aea4f41305882f485669d`;

  const publicClient = createPublicClient({
    chain: mainnet,
    transport: http(RPC_URL),
  });

  const swap = await parseSwap({ publicClient, transactionHash });

  console.log(swap); // Logs the swap details.
}

main();

Development

This repository contains example code that you can run locally, which is useful for the development process. The code can be found in /examples/web/index.html and you can run the code by running npm run web:example.

Contributing

Contributions are always welcomed! Please read the contributing guidelines before submitting a pull request.

Changelog

2.10.2 (2025-06-07)

Bug Fixes

• use log that has taker from transfer for meta txn (9020b47)