Semantic Memory of Browsing history by ArnavLifelessCoder

Your AI-powered second brain for search browsing history by meaning, get instant summaries, discover connections. 100% on-device.

5 (3 reviews)

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About this extension

Semantic Memory is a Chrome extension that makes browser history actually useful. Instead of relying on exact keywords, it indexes the pages you visit using local AI embeddings so you can search by meaning. If you vaguely remember reading "that article explaining transformers" or "the blog comparing PostgreSQL and MongoDB", it'll find it even if those exact words never appeared in the title.

Everything runs locally in your browser by default. Your browsing data never leaves your device unless you explicitly enable encrypted sync. Along with semantic search, the extension can summarize the current page, find similar pages you've visited before, organize your history into a timeline, and show simple analytics about your browsing habits.

Built with Manifest V3, React, TypeScript, IndexedDB, ONNX Runtime, and Transformers.js, with an optional FastAPI backend for encrypted cross-device sync.

Developer comments

Semantic Memory — Privacy-First Semantic Browser History

A Chrome extension that indexes everything you browse using local ML embeddings and lets you query your history semantically — entirely on-device, zero data leaves the browser.
Search by meaning, not keywords
100% on-device by default
Optional encrypted sync

How It Works

You browse the web
       ↓
Content script extracts clean text (Readability.js)
       ↓
Text is chunked (512 tokens, 64 overlap)
       ↓
Chunks are embedded in-browser (MiniLM-L6-v2, ONNX int8, ~23ms/chunk)
       ↓
Embeddings stored in an in-memory vector index + IndexedDB (persisted)
       ↓
You search from the popup: "that article about transformers"
       ↓
Query is embedded → ANN search → ranked results with similarity scores

Everything above runs entirely in your browser. No servers, no API calls, no data leaves your machine.

The optional backend adds:
- Cross-device sync (end-to-end encrypted — server sees only opaque blobs)
- Cross-encoder re-ranking for precision boost
- Topic clustering + knowledge graph (UMAP + k-means)

Features

The popup is organised into four tabs, all powered by on-device ML:

| Feature | What it does |
|---|---|
| Semantic Search | Natural-language search over your history with per-result similarity scores. Matching query terms are highlighted in titles and previews, and results are deduplicated by page (best-scoring chunk wins). |
| Quick Summary | One-click extractive summary + key points of the page you're currently on (centroid-based sentence ranking). |
| Find Similar | Surfaces related pages from your history based on the current page's content. |
| Timeline | Your browsing history grouped by day, filterable by today / week / month / all. |
| Analytics | Total pages, chunks, domains, reading time, and a top-domains breakdown. |
| Settings | Domain blacklist (skip indexing), opt-in encrypted sync config, and data export / clear. |
| Context menu | Right-click selected text → "Search Semantic Memory" (opens the popup pre-filled). |
| Shortcut | Ctrl+Shift+S (Cmd+Shift+S on macOS) opens the popup. |

Recent searches, animated stats, and a live "index active" indicator round out the UI.

Rated 5 by 3 reviewers

Semantic Memory of Browsing history by ArnavLifelessCoder

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