Most efficient Html Parser written in C#?

anyone can recommend some Html Parser written in C#?
open source will be the best.

thank you,

What do you need it to do?

Yes, you going to need to give a bit more details on what you need it to do. If it is well written xhtml code, you can use XDocument or XmlDocument. Both have a .Parse() method

I have no idea if it’s the most efficient one since I’ve only used one parser and not done any comparisons but I like using HtmlAgilityPack. It lets you run Linq queries against the DOM which I like.
However I’ve heard that it has a few bugs.

The HTMLAgilityPack parser is fantastic and is easily the best one I’ve used. Any bugs people do find are often ironed out quickly and I’ve used it in dozens of applications, even in a bespoke search engine for my final-year project.

Outside of rolling your own parser (if you’re mental) I’d give HtmlAgilityPack a huge thumbs up.

And if you were rolling your own, I’d still start with the Agility Pack.