CSS Scan - Instantly check or copy computed CSS from any element for only ~95$
Codacy - Automatically reviews code style, security, duplication, complexity, and coverage on every change while tracking code quality throughout your sprints.
Hoverify - All-in-one browser extension to improve your web dev experience.
SonarQube - SonarQube, a core component of the Sonar solution, is an open source, self-managed tool that systematically helps developers and organizations deliver Clean Code.
CSS Grab n' Go Editor - Visual editor for learning and quick CSS mocking
CodeClimate - Code Climate provides automated code review for your apps, letting you fix quality and security issues before they hit production. We check every commit, branch and pull request for changes in quality and potential vulnerabilities.