Word Rewriter – Chrome Extension

Word Rewriter – Chrome Extension

Inspiration

We frequently encountered complicated language when reading academic or technical publications online, necessitating the opening of a new tab in order to look for more straightforward definitions or explanations. Focus was disrupted and understanding was slowed down by this frequent context shift. That irritation served as the impetus for Word Rewriter, which uses Chrome's built-in AI to rapidly simplify or rewrite text without ever leaving the site.

What it does

With the help of the Word Rewriter Chrome extension, users may quickly:

Give a more straightforward explanation, or
Rewrite it using more precise wording.

With Chrome's new Gemini Nano local AI model, it operates fully on-device, guaranteeing speed, privacy, and offline functioning. For professionals, journalists, and students who wish to better comprehend or communicate concepts while maintaining flow, the extension is perfect.

How we built it

The expansion was constructed using:

Manifest V3 for the construction of Chrome extensions.
For logic and user interface, use JavaScript, HTML, and CSS.
The Rewriter API is one of Chrome's built-in AI APIs for processing text locally.
a modular folder structure that divides content scripts, backend logic, and frontend (UI).
StackBlitz + GitHub for live testing and cooperative development.

Local AI calls are triggered by the popup and context-menu actions, which instantly show the results inside the page overlay after analyzing and rewriting selected text in real-time.

Challenges we ran into

-The new built-in AI APIs in Chrome are currently in preview; learn how to use them.

controlling the asynchronous transfer of messages between background and content scripts.
designing the pop-up to be lightweight and uniform across websites with bright and dark settings.
To safely enable text selection access, debug permissions and manifest settings.

Accomplishments that we're proud of

successfully developed a fully working AI extension that uses local device intelligence and operates entirely offline.
built a user interface that feels native to Chrome and is clear and responsive.
Explain and Rewrite, the two main modes, were implemented with instantaneous contextual output.
Before the formal release, we learned how to use Chrome's AI developer tools.

What we learned

-How browser environments may effectively include AI-powered features. -In productivity extensions, simple UI/UX design is crucial. -The practical aspect of Chrome’s on-device AI processing and how it ensures privacy. -Extension functionality can be made or broken by minute details in the manifest or message.

What's next for Word Rewriter - Chrome Extension

-For accessibility, include spoken output and voice input. -Turn on personalized writing style and tone settings (e.g., formal, friendly, brief). -Encourage summary and translation straight from the extension. -After adding onboarding and refining the user interface, publish on the Chrome Web Store. -For more complex text rewriting operations, integrate with the Gemini Cloud AI fallback.

Built With

chrome-built-in-ai
chrome-developer-tools
chrome-manifest-v3
css
css3
github
html
html5
javascript
rewriter-api
stackblitz
ui

Submitted to

Google Chrome Built-in AI Challenge 2025

Created by

My Contributions:
I designed and built the entire frontend and user interface for the Word Rewriter – Chrome Extension, including the layout, styling, and interaction logic.

UI & Design:
I created the popup interface using HTML, CSS, and JavaScript, focusing on clarity, simplicity, and an elegant dark-themed look that feels natural inside Chrome.
I wrote custom CSS to define the color palette, buttons, hover effects, and smooth animations to make the experience feel dynamic and responsive. The interface uses soft gradients, glass-like panels, and consistent typography to give it a polished, professional look.

Functionality & Logic:
In the UI.js file, I developed all the core logic for how the extension interacts with Chrome.

I implemented:
The ability to fetch highlighted text from the active tab using the Chrome Tabs API.

Communication with the background script through chrome.runtime.sendMessage() for processing the rewrite or explanation request.

A loading state system that prevents duplicate actions and updates button states dynamically.

A copy-to-clipboard feature so users can instantly reuse rewritten text.

Clear status updates (like “Processing…” or “Copied!”) to improve usability and feedback.

These interactions make the tool feel smooth, instant, and reliable which is essential for good user experience.

User Experience & Accessibility:
I added small but important UX touches such as keyboard focus outlines, hover states, and error handling for cases where no text is selected or the tab is inactive. I also made sure the interface adapts visually to different screen sizes and resolutions so it works seamlessly across systems.

Documentation & Write-up:
I also wrote the project’s README and hackathon submission write-up, explaining how the idea came to life, how the extension works, and what challenges I faced during development.
This included describing the integration with Chrome’s Built-in Gemini Nano AI and the Rewriter API, which powers all rewriting locally on the user’s device, ensuring both privacy and speed.

Overall Impact:
Through this project, I combined frontend engineering, Chrome extension architecture, and AI integration to create a tool that helps users instantly simplify or rephrase any text without leaving the page.
My main focus was building an experience that is not only functional but also beautiful, fast, and intuitive, something users actually enjoy using.

Asma Ahmed
IBM Z Student Ambassador | Founder @ LegalAssist | CS (HBSc) Cloud @ Sheridan | President IBM Z Sheridan & UNSA | AI & Full-Stack Dev
Hayden Da Re-Robertson
Zak Ahmad
Kavya M

Updates

Asma Ahmed started this project — Oct 31, 2025 03:35 PM EDT

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