Ranked in these QuestionsQuestion Ranking
Pro Completely open source
Unlike Google Chrome, Chromium is completely open source.
Pro Supports all of Google Chrome features
As Chrome is based on Chromium they overlap in supported features. Chromium syncs between devices, automatically updates, has great built-in developer tools, installs extensions without a restart, includes a combined text bar for entering URLs and searching and has excellent HTML5 compatibility just like Chrome.
Pro Access to Chrome's extensions
Chromium can access the Chrome Web Store and all the extensions hosted there can be installed and used on Chromium.
Chrome and Chromium are available on almost every device nowadays
Every tab and plugin runs in its own subprocess so they will never affect the whole browser ,however that consumes more memory than other browsers
Pro Backed by Google
Chromium was first released as a large portion of Chrome's source code as an open source project by Google in september 2008. The idea was to encourage developers to review the underlying code and to contribute in making Chrome cross platform and port it to Mac and Linux as well.
Nowadays Chromium is a large project with a huge community that's standing behind it but still Google continues to take an extremely active role in Chromium development. This ensures the longevity and constant development and improvement of the browser.
Con High RAM usage
Just like Chrome, Chromium also eats a lot of RAM, which can be a problem for machines with smaller RAM.
Con Lacks privacy options
Con Misses some proprietary multimedia codecs
Unlike chrome, Chromium misses proprietary multimedia codecs per default. There might be some ways over ffmpeg and co but it is still a gray zone. Also by enabling, it also removes one of the core features of Chromium of being open source software
Con Lacks support for certain common media formats
As Chromium avoids bundling any proprietary software, media that requires proprietary codecs or formats such as AAC, H.264, MP3 and Flash will not play by default on Chromium.
Con No official builds
There are no official builds available so you have to rely on a third party distributor
Con Not possible to disable WebRTC
Con Can be dangerous
There are plenty of Chromium distributors and every one of them can disable specific features (like sandboxing) for their build, so you will never know what you get.
Con Simple, dull, bare-boned
Con Doesn't read cookies properly
... and for this reason it only remembers the user logins only in the session. Once the browser is restarted for whatever reason, it forgets everything and the user has to login again everywhere which can become annoying very quickly.