SponsorBlock for YouTube is a browser extension developed by Ajay Ramachandran that allows users to skip over sponsors, intros, outros, subscription reminders, and other annoying parts of YouTube videos. This extension is specifically designed to skip sponsors within videos and does not block normal YouTube ads. It works exclusively on the YouTube website and does not support the YouTube app.

One of the unique features of SponsorBlock is that it is crowdsourced, meaning anyone can submit the start and end times of sponsored segments and other segments of YouTube videos. Once this information is submitted, everyone else with the extension will be able to skip right over the sponsored segment. This open-source extension has a public database, ensuring transparency and accessibility for all users.