Catalog comparison
Visual Regression TrackerLoki
Side-by-side facts from the TestGuild Tool Matcher catalog. Empty cells mean the catalog does not list that attribute — not that the product lacks it.
Open source, self-hosted solution for visual testing and managing results of visual regression testing. Provides backend and frontend application for tracking differences via image comparison with comprehensive integration support.
Open-source visual regression testing focused on Storybook. Runs headless Chrome (including a recommended Docker setup), local Chrome, or mobile simulators/emulators so component screenshots stay reproducible across OS and CI. Aims for easy setup and minimal extra fixture maintenance compared with older PhantomJS-era workflows.
At a glance
Primary testing surface
Visual Regression Tracker
Visual
Loki
Visual
Primary capability
Visual Regression Tracker
Visual
Loki
Visual
License and pricing
Visual Regression Tracker
free · open source
Loki
free · open source
Free trial
Visual Regression Tracker
No
Loki
No
Complexity
Visual Regression Tracker
intermediate
Loki
beginner
Team fit
Visual Regression Tracker
enterprise, large, medium, small
Loki
enterprise, large, medium, small
Test authoring languages
Visual Regression Tracker
.NET, C#, Docker, Java, JavaScript, Python, Shell, TypeScript
Loki
JavaScript, TypeScript
Supported platforms
Visual Regression Tracker
cloud, cross-platform, docker, linux, macos, on-premise, web, windows
Loki
android emulator, chrome in docker, ios simulator, linux, local chrome, macos, storybook, windows
MCP server
Visual Regression Tracker
No
Loki
No
Key features (catalog)
Visual Regression Tracker
Active maintenance and updates, API-driven test automation, Automated test result reporting, Automated visual testing workflows, Azure DevOps integration, Backend and frontend application for image comparison, Baseline image management, Browser protocol testing, CI/CD pipeline integration, Cloud and on-premise deployment options +42 more
Loki
CLI-driven runs and configuration, Designed for reproducible screenshots across environments, Headless Chrome workflow (Docker recommended), iOS Simulator and Android Emulator targets for React Native Storybook, Local Chrome runs for development, No PhantomJS dependency, Visual regression tests for Storybook stories
Limitations (catalog)
Visual Regression Tracker
Docker knowledge required for deployment, Initial setup complexity for enterprise environments, Learning curve for advanced configuration, Limited to visual regression testing, May have performance overhead for large image sets, No cloud-hosted SaaS option available, Requires dedicated server resources, Requires proper image capture setup +1 more
Loki
Centered on Storybook, not full-app E2E visual testing, Docker/Chrome setup needed for the most consistent CI results, Narrower ecosystem than hosted Storybook visual platforms, Teams must manage baselines and review diffs in their own workflow
| Attribute | Visual Regression Tracker | Loki |
|---|---|---|
| Primary testing surface | Visual | Visual |
| Primary capability | Visual | Visual |
| License and pricing | free · open source | free · open source |
| Free trial | No | No |
| Complexity | intermediate | beginner |
| Team fit | enterprise, large, medium, small | enterprise, large, medium, small |
| Test authoring languages | .NET, C#, Docker, Java, JavaScript, Python, Shell, TypeScript | JavaScript, TypeScript |
| Supported platforms | cloud, cross-platform, docker, linux, macos, on-premise, web, windows | android emulator, chrome in docker, ios simulator, linux, local chrome, macos, storybook, windows |
| MCP server | No | No |
| Key features (catalog) | Active maintenance and updates, API-driven test automation, Automated test result reporting, Automated visual testing workflows, Azure DevOps integration, Backend and frontend application for image comparison, Baseline image management, Browser protocol testing, CI/CD pipeline integration, Cloud and on-premise deployment options +42 more | CLI-driven runs and configuration, Designed for reproducible screenshots across environments, Headless Chrome workflow (Docker recommended), iOS Simulator and Android Emulator targets for React Native Storybook, Local Chrome runs for development, No PhantomJS dependency, Visual regression tests for Storybook stories |
| Limitations (catalog) | Docker knowledge required for deployment, Initial setup complexity for enterprise environments, Learning curve for advanced configuration, Limited to visual regression testing, May have performance overhead for large image sets, No cloud-hosted SaaS option available, Requires dedicated server resources, Requires proper image capture setup +1 more | Centered on Storybook, not full-app E2E visual testing, Docker/Chrome setup needed for the most consistent CI results, Narrower ecosystem than hosted Storybook visual platforms, Teams must manage baselines and review diffs in their own workflow |
How the trade-offs apply to your team
Guidance below is inferred only from catalog differences. It is not a winner pick.
Consider Visual Regression Tracker if…
- you need coverage for cloud, cross-platform, docker, on-premise
- your team writes tests in .NET, C#, Docker, Java
- you care about Active maintenance and updates and API-driven test automation
Consider Loki if…
- you need coverage for android emulator, chrome in docker, ios simulator, local chrome
- you want a lower-complexity tool
- you care about CLI-driven runs and configuration and Designed for reproducible screenshots across environments
Questions to verify before choosing
- Confirm current pricing and packaging on the Visual Regression Tracker and Loki websites.
- Trial both tools against a real slice of your application, not a demo site.
- Verify the exact browser, device, or OS matrix you must support.