Glasp is great if you like the social, public-by-default model. If you want a private highlighter where you fully own the data and can integrate it into your own knowledge system (Notion, Obsidian, Supabase), building your own with PlugThis fits better.
Glasp is a social web highlighter Chrome extension that lets users highlight and annotate webpages, save quotes, and share their highlights publicly with a community of readers. It also includes AI-powered features for summarizing and processing highlights.
Pricing: Glasp is free for the core highlighter. Some advanced features may be paid. Their business model includes a community/social layer with public highlight sharing.
Audience: Knowledge workers, students, and curators who read a lot online and want to save and process insights.
| Feature | PlugThis | Glasp |
|---|---|---|
| Pricing | From $29/month | Free (with paid features) |
| Privacy | All highlights stored locally or in your chosen backend | Default public sharing model |
| AI summary | Yes — your own keys | Yes — built-in |
| Social/sharing layer | No (build your own if needed) | Yes |
| Cross-device sync | Use Supabase or Notion as backend (you set up) | Built-in via Glasp account |
| Source code access | Full source | Closed |
| Custom highlight categories | Build any taxonomy you want | Glasp's schema |
| Export highlights | Any format (you build) | Glasp formats only |
Build time: Under 10 minutes
What you get:
Build a Chrome extension called "Personal Highlighter" that lets users highlight and save text from any webpage. The extension should: (1) inject highlight functionality on every webpage — when text is selected, show a small floating "Highlight" button near the selection, (2) on click, save the highlight to chrome.storage.local with: the highlighted text, the page URL, the page title, surrounding context (50 chars before and after), timestamp, and an optional user note, (3) inject visible highlight styling on the selected text (yellow background) that persists when the user revisits the page, (4) provide a popup showing all highlights from the current page with edit and delete buttons, (5) include an options page with an export feature (export all highlights as JSON or Markdown), (6) optional: integrate with Notion API to sync highlights to a Notion database. Permissions: storage, activeTab. Host permissions: <all_urls>. Manifest V3.
Free for core, paid for advanced features
From $29/month + optional API costs if using AI features
On cost, Glasp wins. PlugThis wins on privacy and integration flexibility.
Liner alternative — build your own AI-powered web highlighter and search assistant with PlugThis. from $29/month, your own AI keys.
Notion Web Clipper alternative — build your own clipping extension with AI summary, auto-tagging, and full content. PlugThis, from $29/month.
Remio alternative — build your own AI research and knowledge management Chrome extension with PlugThis. from $29/month, full ownership.
Eightify alternative — build your own AI YouTube summarizer Chrome extension with PlugThis. from $29/month, your own API keys, full code.
Paste the prompt above into PlugThis and ship your custom version in minutes.
Disclosure: PlugThis is a competing product to Glasp. This comparison is intended for users actively evaluating both options. We last verified the Glasp information on this page on 2026-05-14. Pricing and features may have changed since — please check the Glasp website for current details.
Yes — set up a Supabase backend (PlugThis can do this in the build) so highlights sync via your own database. Or save to a Notion database for built-in cloud sync. Either way, you control where the data lives.
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No — those require building a separate web app for sharing, which is outside Chrome extension scope. PlugThis is for the highlighter itself. If you want public sharing, you'd build a web app separately.
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When you revisit a page, the extension reads stored highlights for that URL and re-applies the highlight CSS to the matching text. If page content changes (rewritten article), highlights may not match — handle this by storing surrounding context for fuzzy matching.
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