Top 20 Social Bookmarking Sites to boost your website digitally are-

Pinterest: Pinterest is a visual discovery and bookmarking platform where users can save and organize ideas, recipes, projects, and more on virtual pinboards.

Reddit: Reddit is a social news aggregation, web content rating, and discussion website where registered members can submit content, such as text posts or direct links.

Mix (formerly StumbleUpon): Mix allows users to discover and bookmark content based on their interests, providing a personalized browsing experience.

Flipboard: Flipboard is a personalized news aggregation app that collects articles, images, and videos based on users' interests and presents them in a magazine-style format.

Diigo: Diigo is a social bookmarking tool that enables users to save, annotate, and share web pages, making it easier to organize and collaborate on research and projects.

Delicious: Delicious is a longstanding social bookmarking site where users can save and share bookmarks to web pages, making it easier to access and discover content later.

Digg: Digg is a platform where users can submit and vote on content, determining its popularity and visibility on the site.

Folkd: Folkd is a social bookmarking service that allows users to save and share links to web pages, articles, videos, and images, making it easy to discover and bookmark content of interest.

Pearltrees: Pearltrees is a visual and collaborative bookmarking tool that allows users to organize, discover, and share content in the form of interconnected "pearls" on customizable topic boards.

Scoop.it: Scoop.it is a content curation platform that enables users to discover, curate, and share content on specific topics of interest, helping them establish authority and credibility in their niche.

Instapaper: Instapaper is a bookmarking tool that allows users to save articles and web pages for later reading, stripping away clutter and distractions for a better reading experience.

Pocket: Pocket is a content-saving service that lets users save articles, videos, and web pages to view later across devices, even offline.

We Heart It: We Heart It is a social bookmarking and image-sharing platform where users can discover and collect inspiring images and videos.

Slashdot: Slashdot is a news aggregation website that features user-submitted and editor-evaluated news articles primarily related to science, technology, and geek culture.

BibSonomy: BibSonomy is a social bookmarking and publication-sharing system designed for researchers and scientists to manage and share academic content.

LinkaGoGo: LinkaGoGo is a social bookmarking and web annotation tool that allows users to save, organize, and share bookmarks, notes, and web snippets.

CiteULike: CiteULike is a web service for organizing academic papers and articles, allowing users to bookmark, share, and discover scholarly content in various disciplines.

SiteJot: SiteJot is a simple social bookmarking site that lets users save and organize their favorite websites and links for quick access.

Netvouz: Netvouz is a social bookmarking site that enables users to save, tag, and share bookmarks, helping them keep track of and access their favorite web pages from any device.

BlinkList: BlinkList is a social bookmarking and content discovery platform where users can save, share, and explore web content, blogs, articles, and more.