Best Free Code Review Tools

Next-gen code review with AI fixes. Check code quality and resolve vulnerabilities early. Autofix them in your IDE or via PR. From vulnerability management to penetration testing, secure everything you build, host, and run with Aikido. Your software security HQ. Built for teams of any size, Aikido helps organizations ship secure software –trusted by Revolut, Deel, The Premier League, Tines, n8n, SoundCloud, and 50k more organizations. Aikido gets developers back to building.

GitGuardian is an end-to-end NHI security platform that empowers software-driven organizations to enhance their Non-Human Identity (NHI) security and comply with industry standards. With attackers increasingly targeting NHIs, such as service accounts and applications, GitGuardian integrates Secrets Security and NHI Governance. This dual approach enables the detection of compromised secrets across your dev environments while also managing non human identities and their secrets lifecycle. The platform supports over 450+ types of secrets, offers public monitoring for leaked data, and deploys honeytokens for added defense. Trusted by over 600,000 developers, GitGuardian is the choice of leading organizations like Snowflake, ING, BASF and Bouygues Telecom for robust secrets protection.

GitHub is the world’s most secure, most scalable, and most loved developer platform. Join millions of developers and businesses building the software that powers the world. Build with the world’s most innovative communities, backed by our best tools, support, and services. If you manage multiple contributors , there’s a free option: GitHub Team for Open Source. We also run GitHub Sponsors, where we help fund your work. The Pack is back. We’ve partnered up to give students and teachers free access to the best developer tools—for the school year and beyond. Work for a government-recognized nonprofit, association, or 501(c)(3)? Get a discounted Organization account on us.

ZeroPath (YC S24) is an AI-native application security platform that delivers comprehensive code protection beyond traditional SAST. Founded by security engineers from Tesla and Google, ZeroPath combines large language models with advanced program analysis to find and automatically fix vulnerabilities. ZeroPath provides complete security coverage: 1. AI-powered SAST for business logic flaws & broken authentication 2. SCA with reachability analysis 3. Secrets detection and validation 4. Infrastructure as Code 5. Automated patch generation. any more... ZeroPath delivers 2x more real vulnerabilities with 75% fewer false positives. Our research team has been successful in finding vulns like critical account takeover in better-auth (CVE-2025-61928, 300k+ weekly downloads), identifying 170+ verified bugs in curl, and discovering 0-days in production systems at Netflix, Hulu, and Salesforce. Trusted by 750+ companies and performing 200k+ code scans monthly.

Increase software development and delivery velocity using generative AI assistance, with enterprise security and privacy protection. Gemini Code Assist completes your code as you write, and generates whole code blocks or functions on demand. Code assistance is available in many popular IDEs, such as Visual Studio Code, JetBrains IDEs (IntelliJ, PyCharm, GoLand, WebStorm, and more), Cloud Workstations, Cloud Shell Editor, and supports 20+ programming languages, including Java, JavaScript, Python, C, C++, Go, PHP, and SQL. Through a natural language chat interface, you can quickly chat with Gemini Code Assist to get answers to your coding questions, or receive guidance on coding best practices. Chat is available in all supported IDEs. Enterprises can customize Gemini Code Assist using their organization’s private codebases and knowledge sources so that Gemini Code Assist can offer more tailored assistance. Gemini Code Assist enables large-scale changes to entire codebases.

Code review doesn't have to be so hard. Review Board takes the pain out of code review, saving you time, money, and sanity so you can focus on making great software. You can review just about anything. Code, documents, artwork, you name it! There's more to your project than just code. Documentation, artwork, website designs, interface mockups, release announcements, feature specifications, and the list goes on. A picture paints a thousand words, and can be key in a review. Drag-and-drop one or more images onto your review request to make them instantly reviewable. Your team will be able to click-and-drag anywhere on the image and leave a comment. When they do, you'll see their comment right along with that portion of the image. Made a tweak to the image? Just upload a new revision and view a visual diff of the changes through one of our many image diff modes. Sometimes you'll have other text content that's not part of your source tree.

Sourcegraph is a code understanding platform built to help developers and AI agents search, understand, and evolve large, complex codebases. It provides powerful tools like Deep Search, Code Search, Batch Changes, and Insights to give teams full visibility into how their code works. By enabling natural-language, agentic AI search and exhaustive code navigation, Sourcegraph helps engineers move faster with confidence. The platform supports massive, multi-repository environments across all major code hosts. Sourcegraph is designed to reduce complexity, improve maintainability, and unblock engineering teams as codebases scale rapidly with AI.

CodeSandbox is a cloud development platform that empowers development teams to code, collaborate, and ship projects of any size from any device in record time. Run your code in powerful microVMs and build anything without limits. We configure your environment for you and keep your code always ready, behind a URL. Boxy, the CodeSandbox AI coding assistant, is also now available to all Pro subscribers.

If you are using GitHub Actions for CI/CD and are worried about the security of CI/CD pipelines, StepSecurity platform is for you. Implement network egress control and CI/CD infrastructure security for GitHub Actions runners. Discover CI/CD risks and GitHub Actions security misconfiguration. Standardize GitHub Actions CI/CD pipeline as code files by automated pull requests. Provides runtime security to help you prevent SolarWinds and Codecov CI/CD security attacks by blocking egress traffic with an allowlist. Instant contextualized insight into network and file events for all workflow runs. Control network egress traffic with granular job-level and default cluster-wide policies. Many GitHub Actions are not maintained and are risky. Enterprises fork such Actions, but ongoing maintenance is expensive. By offloading the tasks of reviewing, forking, and maintaining Actions to StepSecurity, enterprises can realize substantial risk reduction and time savings.

Mesa is an AI-powered code review platform designed to help engineering teams improve software quality and ship code with confidence by eliminating technical debt before it reaches production. Mesa’s intelligent agents learn the unique aspects of a team’s codebase, business logic, and development standards to deliver contextual, precise reviews that go beyond simple linting or generic AI suggestions. Users can create custom review agents tailored to specific concerns such as security, performance, and domain-specific logic, and choose from hundreds of underlying models from providers like OpenAI, Anthropic, and Google, optimizing for speed, cost, or intelligence. It generates detailed, consistent pull request descriptions using team templates and integrates directly into existing CI/CD pipelines, adapting to workflows and branching strategies to embed quality checks into everyday development processes.

Kodus is an open source AI-powered code review platform built around an intelligent agent named Kody that integrates directly with Git workflows such as GitHub, GitLab, Bitbucket, and Azure DevOps to help engineering teams automate and improve the quality of their code reviews. Kody analyzes every pull request with deep context-awareness, learning a team’s codebase, architecture, workflows, coding standards, and business rules so it can deliver precise feedback on quality, security, performance, and style rather than generic suggestions. Teams can define custom review rules in natural language or choose from a library of production-tested rules to enforce best practices and consistent standards, with the flexibility to select and run any AI model via their own API keys. Kodus turns unimplemented suggestions into tracked issues, helps monitor technical debt, and offers actionable insights without introducing noise, supporting over 30 programming languages.