1. Gerrit

Gerrit is a web based code review system, facilitating online code reviews for projects using the Git version control system. Gerrit makes reviews easier by showing changes in a side-by-side display, and allowing inline comments to be added by any reviewer. Gerrit simplifies Git based project maintainership by permitting any authorized user to submit changes to the master Git repository, rather than requiring all approved changes to be merged in by hand by the project maintainer.

2. Rietveld

This is one of the best code review tool from Google wherein users can discuss the defects in the code and review the code.

3. Crucible

code reviews = quality code. Review code, discuss changes, share knowledge, and identify defects with Crucible’s flexible review workflow. Its code review made easy for Subversion, CVS, Perforce, and more.

4. Codeplex

Codeplex provides a complete solution for team system code reviews, and this tool and has become very popular with programmers. This code review tool uses the benefits of team system for reducing waste.

5. Barkeep

Barkeep is a fast, fun way to review code. Engineering organizations can use it to keep the bar high. Barkeep is standalone software that you host. Once it’s set up, you can use it to track and code review any number of git repos available on the internet. It’s designed to be easy to run on Ubuntu.

6. Review Assistant

Review Assistant is a code review plugin for Visual Studio. This code review tool helps you to create review requests and respond to them without leaving Visual Studio. Review Assistant supports TFS, Subversion, Git, Mercurial, and Perforce. Simple setup: up and running in 5 minutes.

7. CodeStriker

Codestriker is an open-sourced web application which supports online code reviewing. Traditional document reviews are supported, as well as reviewing diffs generated by an SCM (Source Code Management) system and plain unidiff patches. There are integration points with CVS, Subversion, Clearcase, Perforce, Visual SourceSafe and Bugzilla. There is a plug-in architecture for supporting other SCMs and issue tracking systems.

8. Code Review Tool

Code Review Tool allows team members to review code collaboratively in an easy and efficient manner by removing most of the overhead associated with regular formal code inspections. It provides all the benefits of formal code inspections and requires considerably less effort and time compared to formal code inspections. It supports both formal and lightweight code review processes.

9. Malevich

Malevich is a web-based, point-and-click code review system designed for use by individuals and small teams. Its goal is making the cost of a comment as close to zero as possible: easy commenting encourages thorough code reviews. Reviewing code in Malevich is easy indeed. A reviewer can see both the original as well as the new revision of a file in a browser. To comment on a line of code, he or she simply clicks on that line, and starts typing. Submitting comments makes them visible to the person who requested the code review, as well as to all other reviewers.

10. Code Brag

Codebrag is a simple code review tool that makes the process work for your team.

11. Veracode

Veracode is the world’s best automated, on-demand, application security testing and code review solution. Founded by experts from security companies such as Guardent, Symantec, @stake, and VeriSign, and built on a Software-as-a-Service model – Veracode solutions deliver application security and automated code review services for enterprises that want to cost-efficiently test software security by identifying flaws in applications. Veracode helps developers create secure software by scanning compiled code (also called “binary” or “byte” code) instead of source code.

12. Collaborator

Collaborator is a code review tool that helps development, testing and management teams work together to produce high quality code. It allows teams to peer review code, user stories and test plans in a transparent, collaborative framework — instantly keeping the entire team up to speed on changes made to the code. By enabling team members to work together to review their work, Collaborator can help you catch bugs before your software hits the market.

13. Peer Review Plugin

With Trac’s current set of features, a peer review plugin fits nicely into its lineup. This plugin’s goal is to eliminate the need for time consuming code review meetings by giving developers the ability to review code in a user-friendly web-based environment during their own time. This program is written primarily in Python. The interface integrates seemlessly with Subversion allowing users to browse the repository for reviewable files. Genshi is used as the server-side web-based scripting language with Javascript and AJAX to modernize the user interface.

14. Codifferous

Codifferous can be described as one of the code review tools which is used by busy software developers. Once your code is imported from BitBucket or Github, the software reads the code in a jiffy.

15. Phabricator

Pfabricator can be defined as an open source software engineering platform which includes various open source web applications. These web applications assist software companies for building better software.