Full Answer

Ranking browsers by tracking protection depends on default behaviour, since most users never change settings. On that basis Brave leads: its Shields feature blocks ads, third-party trackers, cross-site cookies, and several fingerprinting vectors automatically, with no configuration. It's the most hostile environment for conventional client-side analytics.

Safari is the next most impactful, partly because of its reach. Intelligent Tracking Prevention blocks third-party cookies, caps script-set first-party cookie lifetimes, and strips known tracking parameters, and Safari's large mobile share means its effect on real-world data is outsized. Firefox follows with Enhanced Tracking Protection on by default, blocking known third-party trackers and cryptominers. Chrome and Edge sit lower for cross-site tracking unless a user enables stricter modes, though Edge's Tracking Prevention still runs by default.

For a WooCommerce operator the exact order matters less than the aggregate. Whichever browser tops the list, the combined effect of Brave, Safari, and Firefox is to remove a fifth to a quarter of the tracking signal you'd otherwise collect, and that share grows as privacy-minded audiences adopt these browsers. You can't dictate which browser a customer uses, so the only control you hold is moving measurement server-side, where your conversion data is recorded regardless of what the browser blocks.