Bro is a small HTML/CSS/JS app runtime. Bro renders web pages with its own layout and paint engine — not by embedding a browser. Broparity measures how close that engine is to Chromium on a curated set of test pages.
Each test case is a UA-neutral HTML page rendered by both engines. We compare the resulting pixels and a structural layout dump (every element's box and a curated set of computed styles). Numbers below are factual and unweighted: this is what bro currently produces, not a target or a claim.
Rendering depends on the host system — fonts, GPU drivers, and OS text shaping all influence the result — so each platform is tracked separately.