User-Agent String
Decode Browser, OS & Rendering Engine • 100% Local
A User-Agent string is a line of text every browser sends with each request, describing itself — but decades of compatibility history have made these strings genuinely messy to read directly. Almost every modern browser's UA string starts with Mozilla/5.0 for historical compatibility reasons that have nothing to do with the actual browser being used, Chromium-based browsers like Edge and Opera include the word "Chrome" in their UA for the same reason, and mobile Safari on iOS includes "like Mac OS X" in its string — all of which makes naive parsing (like simple keyword matching) prone to misreading the real browser or OS.
This tool breaks a UA string into its browser (name and version), rendering engine (the underlying engine that actually renders the page — Blink, Gecko, WebKit, etc., which is often more revealing than the browser name itself, since several browsers share the same engine), operating system and version, and device details (type, vendor, model, where identifiable).
One honest limitation: browsers are increasingly reducing how much detail they put in the User-Agent string by default, in favor of a newer, more privacy-conscious mechanism called User-Agent Client Hints — so on the newest browser versions, some fields here may show up as generic or "Unknown" even though the browser itself knows more detail internally.