Canvas Fingerprinting: Why Clearing Cookies Won't Protect You Canvas fingerprinting exploits subtle hardware rendering differences to create persistent browser identifiers. When a website instructs your browser to draw content using the HTML5 Canvas API, the pixel output varies slightly based on your GPU and graphics drivers. This variation creates a unique device fingerprint that is regenerated on every visit — nothing is stored, so there's nothing to clear. **Why cookie deletion doesn't help**: The fingerprint comes from how your hardware renders graphics, not from stored data. Private/incognito mode and VPNs don't change this. **The solution**: Per-profile fingerprint spoofing injects deterministic noise into canvas rendering so each browser profile generates a different but internally consistent fingerprint. Tools like FireKey implement this approach for developers who need genuine browser isolation. Test your exposure: visit browserleaks.com/canvas and compare your canvas hash across private windows — you'll find they're identical.