Install

Get Glossa running in a minute.

Works in Chrome, Edge, Brave and Arc, version 116 or newer.

  1. DownloadDownload Glossa (zip) and unzip it.
  2. Open extensionsGo to chrome://extensions and switch on Developer mode in the top-right corner.
  3. Load itClick Load unpacked and choose the unzipped folder. A welcome tab opens with a practice paragraph.
  4. Pin itOpen the puzzle-piece menu in the toolbar and pin Glossa so it’s one click away.

Ways to explain

Do thisResult
Select text, press ⌥E (Mac) or Alt+EThe meaning opens in the side panel
Click Explain next to the selectionSame, with the mouse
Right-click the selection → Explain “…”Same, from the context menu
Press ⌥⇧E / Alt+Shift+EOpen the side panel
Click the toolbar iconQuick lookup, pause, per-site settings

Shortcut taken by another extension? Open chrome://extensions/shortcuts and choose a new one for “Explain the selected text”.

Use your own API key

The free plan needs no setup. For unlimited use, open the side panel → Settings → My own API key, pick a provider, paste your key and press Save and test. You can also try your key on the homepage first.

ProviderWhere to get a key
OpenAIplatform.openai.com/api-keys
Anthropicconsole.anthropic.com
Groqconsole.groq.com/keys
Google Geminiaistudio.google.com/apikey
OpenRouteropenrouter.ai/keys
CustomAny OpenAI-compatible server (Ollama, LM Studio, vLLM…). Enter its base URL in the extension.

Your key is stored only in your browser and sent only to that provider.