Shajan Jacob

Shajan Jacob

Tech Lead
Jul 19, 2026

Co Apply

Intelligently autofill forms on any website using your data and AI.

ai web browser-extension autofill deepseek
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AI-powered browser extension that intelligently fills forms on any website using your data and a knowledge base powered by DeepSeek.

Built for Firefox (Manifest V3).

How it works

  1. Configure your data, FAQ entries, and API key in the extension settings.
  2. Open any page with a form. A floating "Auto Fill" button appears.
  3. Click the button. Co Apply extracts all form fields, sends them to DeepSeek along with your data, and fills the form.
  4. Review each field -- green badges mark filled fields, orange badges mark fields left empty. Submit manually.

Screenshots

Extension settings showing user data configuration
User data and FAQ configuration
Extension settings showing LLM and API key configuration
API key and model settings
Form being autofilled with green and orange verification badges
Form fields filled with verification badges

Features

  • Broad form detection -- works with inputs, textareas, selects, radio buttons, checkboxes, contentEditable elements, and ARIA widgets, even outside <form> tags.
  • AI field understanding -- DeepSeek interprets labels, placeholders, ARIA attributes, and nearby text to match fields to your data.
  • User data -- store any information you commonly use (name, contact, experience, preferences, etc.) in freeform text.
  • FAQ / Knowledge base -- reusable answers for open-ended questions like "Tell us about yourself".
  • File attachments -- attach files (CV, certificates, etc.) for upload fields. File contents stay local, only names and descriptions are shared with the AI.
  • Verification badges -- numbered green/orange badges persist on each field after filling so you can review before submitting.
  • Website allowlist -- restrict the extension to specific domains, or leave empty to enable everywhere.

Getting started

  1. Install the extension in Firefox.
  2. Open the settings page and enter your DeepSeek API key.
  3. Add your data under the Data tab -- include anything you'd want filled into forms.
  4. Optionally add FAQ entries and attach files.
  5. Configure the extension to allowlist the website you want to use it on.
  6. Navigate to any website(configured in the extension settings) with a form and click the "Auto Fill" button.

Requirements

  • Firefox 115 or later
  • A DeepSeek API key