ChatDuel

English full name: ChatDuel - Split-Screen Multi-AI Comparison Workspace 中文完整名： ChatDuel - 多 AI 同步问答与横向对比工具

A Chrome extension that lets you compare answers from multiple AIs side by side on a single page. It is not an API aggregator and needs no API key — instead it drives the official web UIs you are already logged into (by embedding them in iframes).

Supported AIs

• ChatGPT
• Claude
• Gemini
• Doubao (豆包)
• DeepSeek

You can show up to 3 panels at the same time.

Install

Get ChatDuel from your browser's extension store:

• Chrome: https://chromewebstore.google.com/detail/chatduel/ggddfpmgeppjejfanaloopfpiiakljjl
• Edge: https://microsoftedge.microsoft.com/addons/detail/chatduel/jnnocldpbodbnnkojbdklkgcoeiajekk

Features

• Shared input box — type once at the bottom and send to all enabled AIs at once.
• Pending question management — while answers are being collected, queued questions can be edited, deleted, and reordered before they are sent. A queued question may include one attachment that can be reviewed, removed, or replaced; queued attachments are limited to 50 MB in total. The queue stays hidden until at least one question is pending.
• Target a specific AI — prefix with @chatgpt, @claude, @gemini, @doubao, @deepseek, or use the @-candidate menu, to send to just one.
• Panel management — each AI's title bar can switch or close the AI in that slot; "Add AI" brings hidden AIs back. If the target AI is already shown, the two panels swap positions.
• Attachments — images, TXT and CSV (sent as inline text), plus Markdown, HTML, PDF, Word, and Excel as real uploaded files. Other/unrecognized file types are attempted automatically too (a direct-upload attempt, then a paste fallback) unless the target platform rejects them, in which case they fall back to manual upload. Executable/script files (.exe, .sh, etc.) are blocked outright.
• Forwarding — pick one or more past answers from an AI and forward them to another AI for interpretation.
• Summarizing — select several Q&As from history, choose which AIs take part, and let a chosen AI write a comparison summary. "Final conclusion / disagreements only / short summary / combined opinion" each have their own configurable prompt.
• History records — per submission, saves the question, actual sent content, attachments, and AI replies, for review, per-block copy, Markdown export, summarizing, and forwarding. Markdown export restores headings, lists, and paragraphs where possible.
• History-save recovery — if a local history record fails to save after an answer is captured, the pending queue pauses and offers "Retry saving history" or "Continue without saving", so you can recover the save or move on without losing the in-flight answer.
• Official-site sessions — saves the official conversation URL and the AI state shown at the time, so you can restore the panels and reopen an old chat to continue.
• Update reminder — after ChatDuel is upgraded, the next extension page shows a one-time reminder to refresh any AI website tabs that were already open. ChatDuel never refreshes or closes those tabs automatically.
• Languages — the UI, help text, and default prompts switch among 中文 / English / Français / Deutsch / Svenska / Norsk / Nederlands / 日本語 / 한국어. Your saved prompts are not overwritten by language switching unless you click "Restore current prompt defaults".

Records vs official-site sessions

	Records	Official-site sessions
What it saves	User question, actual sent content, attachments, AI replies	Official conversation URL (ChatGPT / Gemini / Doubao / DeepSeek / Claude) + AI state shown at the time
Main use	Review each round, copy per block, copy/export Markdown, summarize, forward	Restore panels and reopen an old official chat to continue

In short: to look back at a past AI answer, use Records; to return to an old official conversation, use Official-site sessions.

Usage help

The settings button (bottom-left of the extension) has a "Usage help" tab explaining sending, attachments, panel management, forwarding, summarizing, records, and official-site sessions. The "Display" tab switches the UI language and re-detects status; the "Prompts" tab uses a dropdown to pick the template to edit. When adding features later, update both this help and this README.

Disclaimer & Limitations

• Not an API aggregator. ChatDuel does not require or use any API keys. It drives the official web UIs you are already logged into.
• No affiliation. ChatDuel is an independent open-source project and is not affiliated with, authorized, or endorsed by OpenAI, Google, Anthropic, ByteDance, DeepSeek, or any other AI provider.
• Compatibility notice. Because ChatDuel relies on the official web interfaces of third-party AI providers, future updates, DOM changes, login-flow changes, or Content Security Policy (CSP) adjustments by those providers may temporarily affect or break compatibility. We fix breakages as they are reported, but cannot guarantee uninterrupted operation.

Permissions

ChatDuel requests only the permissions it needs:

Permission	Why
storage	Save your records, official-site sessions, and settings locally.
unlimitedStorage	Allow large conversation histories and attachments to be stored without hitting the browser's standard storage quota.
tabs	Detect which AI site is open and drive the correct panel.
declarativeNetRequest	Keep the extension working with the official sites (e.g. cookie/header adjustments for specific platforms).
alarms	Periodically refresh the remote selector configuration.

Host permissions are limited to the official AI sites plus https://chatduel.ifeeling.app/* (the project's own website, used to fetch selector updates). No <all_urls> is requested.

Development

npm install
npm run dev        # start the vite dev server; load dist/ in chrome://extensions
npm test           # unit tests (not included in the public repo — see CONTRIBUTING.md)
npm run test:e2e   # e2e tests (not included in the public repo)
npm run typecheck

Load into Chrome / Edge

1. npm run build
2. Open chrome://extensions or edge://extensions
3. Enable "Developer mode"
4. Click "Load unpacked" and select the dist/ folder

License

Released under the MIT License.

See also: Privacy Policy · Contributing · Security Policy · Changelog