Help / Core workflow

Look up words in a PDF

Open a PDF in your browser and double-clicking a word does nothing. That's because the built-in PDF viewers in Chrome, Edge and Firefox block every extension, not just Anki Dictionary. The fix is to open the PDF in a viewer that runs as a normal web page.

Open the PDF in the PDF.js web viewer

PDF.js is the free, open-source viewer made by Mozilla (the same one built into Firefox). Its web version is an ordinary page, so Anki Dictionary works on it in any browser it supports.

  1. Save the PDF to your computer if it's online.
  2. Open mozilla.github.io/pdf.js/web/viewer.html in your browser. It opens with a sample document.
  3. Drag your PDF onto the page. Or click the » button in the top right, choose Open and pick the file. The file opens in your browser and isn't uploaded anywhere.
  4. Double-click any word (or use your trigger key) to look it up, then add it to Anki with its sentence as usual.
A French reading PDF open in the PDF.js web viewer, with the » menu expanded and Open highlighted

Opening a PDF from the » menu.

Anki Dictionary lookup popup for the French word bavardant, double-clicked in a PDF in the PDF.js web viewer

Double-click a word and the lookup appears, with the sentence as context.

Tip: bookmark the viewer page so it's one click away next time.

If it still doesn't work

  • You can't select the text. The PDF is a scan (pictures of pages), so there's no text to look up. Run it through an OCR tool first to add a text layer.
  • The page was open before you installed. Refresh it. See refresh pages after installing.

More getting-started guides