In this article, you’ll find the complete list of top industry-standard smart contract auditing tools to use during your smart contract audit.

We’ve tried 10s of tools and selected each tool in this guide based on its unique capabilities, ranging from in-depth static analysis to advanced on-chain monitoring functionalities.

The demand for smart contract auditing has drastically increased due to crypto-related crimes. A total of $3.3 billion was lost in transactions to such crimes in 2022 alone, highlighting how crucial it is to ensure that smart contracts are free from vulnerabilities.

A Smart Contract Audit involves line-by-line analysis, stressing, testing, and understanding of smart contracts or codebases done by smart contract auditors through manual reviews and automated tests.

Using appropriate security tools is essential for identifying vulnerabilities in smart contracts. Here you’ll find the ultimate list of top smart contract auditing tools that stand out in terms of reliability and effectiveness to help you while auditing your smart contracts.

What is a Smart contract auditing tool?

Smart Contract Auditing Tools play a crucial role in detecting vulnerabilities within smart contracts.

They not only pinpoint critical vulnerabilities but also assist in optimizing gas usage. These tools are invaluable for auditors, auditing companies, developers, and anyone keen on ensuring their smart contract's robustness and security.

Auditing tools come in various forms, including static analyzers, mutation testers, fuzzing tools, formal verification systems, and visualization tools.

Let's delve into the top smart contract auditing tools that enhance and streamline the smart contract auditing process.

1. Solodit - The One Stop Learning Tool for Security Auditors

Solodit, powered by Cyfrin — one of the leading Web3 Security firms, serves as a comprehensive aggregator of findings from renowned audit platforms and solo auditors, making it an ultimate one-stop learning shop for web3 security auditors.

The tool, open-source and completely free to use, allows users to delve into historical reports, offering insights into past exploits, their severity, and the latest bugs reported across web3. This enables auditors to stay up-to-date and make informed decisions when assessing smart contract security

Drawing data from 17+ notable sources, including Sigma Prime, Spearbit, Trail of Bits, and Code4rena, Solodit, and used by every top-auditor and auditing firm world wide stands out as a valuable auditing tool for web3 security auditors.

Key Features

• Solodit consolidates audit reports from 17 sources (8000+ findings), offering a singular platform for web3 security auditors.

• Users can filter their search results based on various criteria such as the source, impact level, protocol name, report tags, quality scores and more.

• Solodit is super quick, allowing auditors to search through findings in ~1 second, ensuring timely access to crucial information.

• Solodit also hosts a **Telegram community group** where auditors can engage in discussions about bug bounties, collaborate, and connect with leading auditors globally.

2. Slither

Slither stands as the first static analysis framework for Solidity. It is designed to detect vulnerabilities easily, offering both a visual overview of contract complexities and an API and tools for custom analysis.

With its capability to identify over 80 distinct vulnerabilities, including suicidal, reentrancy, and timestamp issues, Slither ensures robust code security.

Being open-source, Slither not only identifies vulnerabilities but pinpoints their exact location in the source code, all within seconds and without manual interventions.

Its adaptability and comprehensive set of tools make it a go-to for analyzing Solidity code.

Key Features

• Slither provides precision in detecting vulnerabilities with minimal false positives.

• It pinpoints error occurrences directly in the source code.

• Allow seamless integration with Hardhat and Foundry builds.

• Provides results on averaging under ~1 second per contract analysis.

• Utilizes SlithIR for high-precision, straightforward analyses.

• Slither is also compatible with Github's code scanning via CI.

3. Aderyn

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Aderyn, powered by Cyfrin ADD LINK is a Rust-based Solidity AST analyzer and context builder.

Key Features

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4. 4naly3er

4naly3er stands out as a comprehensive tool for auditing smart contracts. It’s an open-source static analyzer built in Typescript, aiming to delve deep into smart contract codebases to pinpoint vulnerabilities and areas of concern.

It uses both RegEx and AST methods, and also includes features from Openzeppelin's solidity-AST for a complete check.

Key Features

• Unlike dynamic analyzers that run the code to find vulnerabilities, 4naly3er statically examines the code without executing it, ensuring a safe and efficient analysis.

• After analyzing, 4naly3er generates detailed reports that are easy to understand, helping developers quickly identify and rectify potential vulnerabilities.

• The tool is equipped to analyze smart contracts from various blockchain protocols, enhancing its versatility and applicability.

5. Echidna

Echidna, developed by Trail of Bits, is a tool designed for testing Ethereum smart contracts. Unlike traditional testing tools that look for crashes, Echidna focuses on finding breaks in specific rules set by users, known as invariants.

Using the contract's ABI (Application Binary Interface), Echidna validates the smart contract by providing invalid or unexpected inputs to observe how the smart contract reacts to those inputs.

What is Fuzz Testing or Fuzzing?

Fuzz testing is like a stress test for software. It involves giving a program lots of unexpected inputs to see if it breaks or behaves unexpectedly. The goal is to find weak spots in the smart contract.

Read what is Fuzz and Invariant Tests to know more about fuzz testing.

Key Features

• Echidna designs its tests based on the user's specific Ethereum smart contract, ensuring targeted testing.

• The tool adjusts its approach, focusing on areas where it detects potential vulnerabilities to uncover deeper issues.

• It simplifies detected problems, helping developers pinpoint and address the root cause faster.

• Lastly, it reports on how much gas or computing power is used by the tests.

6. Mythril

Mythril is one of the leading security analysis tools for Ethereum smart contracts. It empowers smart contract auditors to identify a wide range of security vulnerabilities, including but not limited to issues like integer underflows.

By combining techniques like symbolic execution, SMT calculation and taint analysis, Mythril provides a comprehensive audit of Ethereum bytecode.

Mythril offers insights into the root causes of these issues, ensuring developers have a clear understanding of potential risks, such as numeric overflows or function re-runs. Its adaptability and thoroughness make it an indispensable tool for anyone serious about smart contract security.

Key Features

• Mythril uses a detailed method to inspect Ethereum code. By examining every possible way the code might work, it aims to uncover any potential issues or vulnerabilities.

• The tool comes with a set of built-in vulnerability analysis modules that can detect common vulnerabilities in Ethereum smart contracts

• For those with specific needs, Mythril allows users to create and add their own checks, offering a level of customization.

• To help with tracking and reviews, Mythril saves the results of each test. This means users can revisit and analyze past tests whenever they need to.

7. Solidityscan

SolidityScan is the flagship product of Credshields. It is an automated smart contract vulnerability detector that allows developers to scan their smart contract, fix the vulnerabilities and publish the audit report in a single click.

With more than 3500+ user base and 131 vulnerability patterns, SolidityScan is unbeatable in the market right now.

It has scanned over 16,000,000 lines of code and secured $2.2B till now.

Key Features

• Users can initiate a smart contract scan from a wide range of supported protocols and receive a quick analysis report within seconds.

• Solidityscan supports a variety of protocols, including Ethereum, Polygon, Avalanche, Binance, Fantom, Celo, and many more.

• Users can customize issues, silence specific issues, or add their own rules.

• The tool can also integrate with popular tools like Slack and JIRA to send out alerts or raise issue tickets

8. Halmos

Halmos is a symbolic testing tool for EVM smart contracts. A Solidity/Foundry frontend is currently offered by default, with plans to provide support for other languages, such as Vyper and Huff, in the future.

You can learn more about halmost on the official Symbolic testing with Halmos guide on the a16z website.

Key Features

• Symbolic Testing: Halmos employs symbolic testing which runs tests with symbolic inputs, checking the program for all possible inputs. This is different from traditional testing which only verifies a program for a limited set of inputs.

• Automatic Verification: Running tests through Halmos will automatically verify they pass for all possible inputs, or provide counterexamples if they don't.

• Incremental Improvement: Developers can improve their tests incrementally, a few specifications at a time, without having to start from scratch. This facilitates a gradual transition to formal verification.

9. Manticore

Manticore is a symbolic execution tool for analyzing smart contracts and binaries. It offers a platform for the detailed analysis of programs, allowing auditors to explore all possible states a program can reach.

Manticore is versatile and can be used for various types of programs, including Ethereum smart contracts, Linux ELF binaries, and WebAssembly modules.

Key Features

• Manticore evaluates programs using symbolic inputs, ensuring a complete exploration of all potential outcomes.

• It can automatically generate concrete inputs that lead to specific program states.

• Manticore is proficient in identifying issues, including crashes in both binaries and smart contracts, ensuring robust program performance.

• Auditors have the flexibility to control the analysis process via event callbacks and instruction hooks.

10. ZeppelinOS

ZeppelinOS, introduced by OpenZeppelin, is an innovative platform designed for smart contract application development. As an open-source and distributed system, it’s built on the EVM and offers tools and services to ensure the creation and management of secure smart contract applications.

Key Features

ZeppelinOS consist of 4 main components:

• Kernel: The central component of ZeppelinOS, the Kernel offers a set of upgradable smart contract libraries, overseen and updated by the community.

• Scheduler: This feature enables scheduled tasks within the EVM. Contracts can set up functions to run later, and participants can pay the associated gas fees, earning compensation in return.

• Marketplace: Designed to enhance connectivity between decentralized apps, the Marketplace ensures different smart contract projects can interact smoothly, promoting faster growth of decentralized applications.

• Off-Chain Tools: ZeppelinOS provides a suite of tools that operate outside the blockchain, aiding developers in various stages of app development, from initial coding to final deployment and ongoing monitoring.

11. Foundry

Foundry is a streamlined tool designed for smart contract development and auditing. It simplifies tasks like managing project dependencies, compiling, testing, deploying and direct blockchain interactions.

Foundry offers features like automatic compiler version detection and efficient caching, and it stands out with its fuzz testing capabilities.

Key Features

It is made up of several different tools that work together to make building and testing Ethereum applications easier, which include:

• Forge: An Ethereum application testing framework that supports property-based testing.

• Cast: Assists users in engaging with and managing smart contracts on the Ethereum blockchain.

• Anvil: A local Ethereum node, facilitating users in application testing without relying on external networks.

• Chisel: Solidity REPL tool, enabling users to swiftly test and execute Solidity code, enhancing the development experience.

12. Diligence Fuzzing

Diligence Fuzzing is a specialized platform for auditing smart contracts on Ethereum. It supports fuzzing, a technique to uncover vulnerabilities by testing contracts with a wide range of inputs.

With its integration capabilities, auditors can seamlessly use it alongside tools like Foundry.

It uses Harvey, a powerful fuzzer for Ethereum’s bytecode, which delves deep into the contract codes, mutating and testing various inputs to identify potential issues.

Key Features

• Harvey is skilled at analyzing Ethereum bytecode, identifying code anomalies and vulnerabilities with high efficiency.

• Auditors can integrate their existing Foundry tests with Diligence Fuzzing, streamlining the auditing process and minimizing setup hassles.

• Auditors can use Scribble to annotate contracts, highlighting critical code sections, preparing the testing environment, and initiating in-depth code reviews with Diligence Fuzzing.

13. MythX

MythX, developed by Consensys, is a robust security analysis platform for smart contracts. It’s designed to identify a wide range of security vulnerabilities by employing a combination of static analysis, dynamic analysis, and symbolic execution.

MythX specializes in scanning Ethereum and other EVM-based blockchain smart contracts to ensure their security.

Key Features

• MythX stands out as one of the first tools capable of both symbolic execution and fuzzing, ensuring a thorough review of projects.

• It provides various tools for auditing smart contracts, such as:

  • MythX CLI: A unified command-line interface for easy access to MythX features.

  • MythX-JS: A Typescript library, allowing integration of MythX into Javascript or Typescript projects.

  • PythX: A dedicated library for integrating MythX functionalities within Python projects.

  • MythX VSCode: An extension for the VS Code editor, enabling direct smart contract scans and result viewing within the editor.

• MythX also works with popular tools like Remix, Whiteblock, and Guardrails, enhancing its utility in the smart contract development ecosystem.

Conclusion

Smart contract auditing tools are essential for quickly identifying vulnerabilities. However, auditors should not completely rely on them.

A thorough audit combines both automated tools and manual code reviews. Platforms like Codehawks offer auditors an opportunity to refine their skills and receive rewards for detecting vulnerabilities. It's crucial to adopt a comprehensive approach for effective smart contract security.