List of free code-review stuff for developerππ½
If you're looking for all programming tools around code-review (not just free). Check this page List of code-review Programming Tools

DeepSource
DeepSource helps you write clean code on every pull-request. Built for teams who move fast and donβt break things.
Tag: code-review, clean-code
Unlimited public repositories Unlimited lines of code analyzed Unlimited private repositories for individual accounts 1 private repository for teams/organizations Continuous analysis with GitHub, GitLab, and Bitbucket 3 team members

Viezly
Viezly helps you review code easier with enhanced navigation and review helpers
Tag: code-review, clean-code, diagram
Free for open source repositories Free for personal usage

Codiga
Coding assistant for VS Code and Jetbrains and automated code reviews for GitHub, GitLab and Bitbucket.
Tag: code-review, code-analysis, code-snippet, coding-assistant
Free for individuals, open-source projects and small teams
Unlimited repositories Instant code refactoring 25,000 tokens / ~10 PRs Rate limited

SonarCloud
Enhance your workflow with continuous code quality, SonarCloud automatically analyzes and decorates pull requests on GitHub, Bitbucket, Azure DevOps and GitLab on major languages.
Tag: clean-code, security, code-review
Free for public projects Unlimited lines of code Anyone can see your project and browse your code You have access to the full SonarCloud feature set Choose members of your team who can work on your projects

Livecycle
Make your pull requests remarkably contextual, collaborative and efficient.
Tag: code-review, collaboration, productivity
Free for up to 5 collaborators. And free forever for open source projects.

Users: 5 Most Recently Active Branches: 10 Most Recently Active Merge Conflict Detection: On Fetch/Pull Priority Support: none

Code Climate Quality
Quality by Code Climate provides automated code review for test coverage, maintainability and more so that you can save time and merge with confidence.
Tag: code-review, quality-assurance
Free forever for open source Unlimited public repositories Unlimited users GitHub pull request integration
For <4 seats Unlimited private repositories Everything in the team plan up to 4 seats

CoderMirror
Plugin for your IDE that tracks and analyzes your activity to create reports on your coding and personalized learning material.
Tag: code-review