Note Bridge is data migration software for knowledge workers who need to move their entire OneNote and Obsidian library into Notion without losing content. It is a web app, not a desktop tool or a browser extension. You sign in with Microsoft and Notion, scan your notebooks, see exactly what will move and how much it costs, and run the migration in the background. You get an email when it is done. The product exists because the existing free routes work fine for small notebooks but break down at scale. Notion's zip import is capped at 5MB on the free plan. The Obsidian Importer hits Microsoft Graph API rate limits, has no progress bar, and can take hours on a 1500-page notebook. Audio attachments and ink strokes do not survive a Notion zip import. Tables nested inside bullet lists, code blocks, or blockquotes break during conversion. Note Bridge was built to handle the cases the free tools drop. What it preserves: notebook → section → page hierarchy, images, PDFs, tables, audio attachments, ink drawings rendered to SVG, LaTeX equations, and arbitrary file attachments. It uses the Microsoft Graph API to read OneNote and the official Notion API to write. Pricing is tiered by total page count of a single migration: Free up to 20 pages, Personal $9 up to 200 pages, Pro $29 up to 1,500 pages, Power User $79 up to 5,000 pages, Business custom for 5,000+. Price scales smoothly between tiers, so you only pay for what you need. An empty-delivery auto-compensation system refunds credits for any page that arrives empty in Notion. Note Bridge is listed on the official Notion Integration Gallery and available in eight languages. Best fit: heavy OneNote or Obsidian users with 200+ pages who cannot afford to lose content.