Free DaltonLens Alternative
DaltonLens is a comprehensive color blindness simulator available both as a desktop application and an online web tool. The project focuses on providing scientifically accurate CVD simulations using established algorithms. The online version allows you to upload images and see how they appear under various color vision deficiencies without needing to install software. While DaltonLens is a powerful tool with desktop app options for advanced users, Fixie's Color Blind Simulator offers a streamlined web-first experience with comparison modes optimized for quick accessibility testing.
Try Color Blind Simulator Free →Color Blind Simulator vs DaltonLens
| Feature | Fixie Color Blind Simulator | DaltonLens |
|---|---|---|
| Price | Free forever | Free (open source project) |
| Signup Required | No | No |
| Platform | Web only (works everywhere) | Web + desktop apps (Windows/Mac/Linux) |
| Processing Location | 100% client-side (browser) | Client-side (browser for web version) |
| CVD Types Supported | 7 types (full + partial + Achromatopsia) | Multiple CVD types with scientific accuracy |
| Side-by-Side Comparison | Before/after slider + grid view | Sequential or split-view depending on mode |
| Color Picker Mode | Yes (test colors directly) | Image-focused |
| Desktop App | No (web only) | Yes (advanced features) |
Why Choose Fixie?
DaltonLens is a well-respected open source project built by developers who care deeply about accessibility and scientific accuracy. The online simulator uses established CVD algorithms and provides reliable results for testing how designs appear to people with color vision deficiencies. For users who need advanced features like real-time screen filtering or integration into desktop workflows, DaltonLens offers downloadable applications for Windows, Mac, and Linux.
The desktop apps are particularly valuable for developers and designers who want to test entire desktop applications or operating system interfaces. However, for many use cases — testing a website design, verifying marketing materials, or checking infographics — installing a desktop app is more friction than necessary. The web version solves this, but still requires navigating between different simulation types to compare results.
Fixie's Color Blind Simulator is designed purely for web-based accessibility testing. The interface focuses on comparison modes: a before/after slider for presenting changes to clients or stakeholders, and a grid view that shows all seven CVD types simultaneously for fast audits. You can test individual colors without creating mockup images, which is useful when building design systems or choosing brand palettes. Both tools are free and scientifically accurate — DaltonLens offers more platform options and advanced features, while Fixie optimizes for fast, web-first accessibility checks.
How to Use Color Blind Simulator
Step 1: Open the Color Blind Simulator
Visit fixie.tools/color-blind — no installation, no account, no desktop app required. Works instantly in any modern browser.
Step 2: Upload an Image or Use Color Picker
Upload your design (website screenshot, marketing asset, infographic) or use the color picker to test specific color combinations. All processing happens in your browser — no server uploads.
Step 3: Choose Your View Mode
Select the before/after slider to compare normal vision against any CVD type with an interactive slider (great for demos). Or switch to grid view to see all seven deficiency types at once (faster for comprehensive audits).
Step 4: Download Simulations
Download individual CVD simulations or click "Download all" to save every type as separate files. Perfect for accessibility documentation, client presentations, or compliance reports.