Lumen AIAI Sidebar Assistant
Free AI Sidebar Assistant No-Ads Bring Your Own API Key No Subscription Fee
Please read before installing

This is a browser sidebar extension. Click button to go to official extension store for installation.

Lumen AI is a Chrome & Edge sidebar extension. Installation takes place on the official extension store. No software or file is downloaded from this page.

Get it on Chrome Web StoreChrome Web Store · Free Get it for Microsoft EdgeEdge Add-ons Store · Free
Chrome Web Store Edge Add-ons

No sign-up. No subscription fee. Use your own AI API key.

Simple, powerful features. Accurate AI translation. A lightweight no-ads browser AI tool, popular among users who read, translate and take notes on the web.

Installing now? See the models available with free trial credits

Your AI Sidebar Assistant for Every Web Page

Lumen AI is a free AI sidebar assistant for Chrome and Edge. Get web-page summarization, web translation for foreign trade, and free AI chat for browser reading — without leaving the page you are on.

Example
Features

A focused toolkit, right in your sidebar

An ai sidebar assistant for reading, writing and research. All features run in your browser sidebar on Chrome and Edge — no account, no ads, no subscription.

Ask about selected text

Select any text on a web page and ask AI about it. Follow-up questions keep the multi-turn conversation context.

Web page & bilingual translation

Translate a selected phrase or the whole page. Side-by-side bilingual reading for foreign trade translation work.

Quick local notes

Jot down notes while you browse. Notes are saved locally in your own browser, not on a server.

Screenshot & image text

Upload a screenshot to ask AI about the image, or extract text from it for reading and translation.

Detect & save page media

Detect audio and video resources on the current page and save them locally when you need them.

Connect your AI provider

Works with major AI providers through your own API key. You choose the model and the provider.

Whether you need a chrome ai sidebar extension or an edge ai sidebar, Lumen AI combines a webpage summarizer, web page translation, free AI chat for browser and a foreign trade translation extension in one no-subscription ai extension.

Limited-time install offer

Install now and get free trial credits

New installs include free trial credits you can use with the models below. The extension itself stays free — no subscription and no ads.

Models available with the free credits

  • DeepSeek-V4.1-Flash-1017
  • NVIDIA-Nemotron-3.5-Super-VL
  • MiMo-V2.6-Flash
  • GLM-5.3-Flash
  • gemma-4-26B-A4B-it
  • gemma-4-31B-it
  • and more models

About this offerOffer terms, credit amount and validity are shown inside the extension before activation. Free credits are optional — you can keep using your own API key with any supported provider at any time. The extension itself remains free and Lumen AI does not charge for it.

Privacy & Security

No backend. No data collection. Your key stays yours.

Lumen AI has no backend server. Your privacy is built into the architecture, not added as a promise.

Zero backend server

The extension has no server of its own. There is no Lumen AI service that your data could be sent to.

No chat or browsing data collected

We do not collect your chat content, browsing history, page content or notes.

API key stored locally

Your API key is stored only in your own browser and is never uploaded to any server of ours.

Direct requests with your own key

When you use your own API key, AI requests are sent directly from the extension to the AI service provider you selected. Promotional free credits are a separate optional offer.

How a request travels

Your browserLumen AI sidebar extension
Your own API keyStored locally in the browser
Your chosen AI providerThe service you picked

✗ No Lumen AI server in between. ✗ No user data uploaded to us.

The extension itself is completely free — no ads, no subscription fee and no registration. Beyond any promotional free trial credits, AI usage costs are charged by your own API service provider according to that provider's pricing, not by Lumen AI.

FAQ

Frequently asked questions

Do I need to register an account?

No. There is no sign-up, no account and no login. Install the extension, enter your own AI API key in the sidebar settings, and it is ready to use. This is a no-subscription ai extension.

Will you collect my browsing history or chat data?

No. Lumen AI has no backend server and does not collect your chat content, browsing history, web page content or notes. Your API key is stored locally in your browser. AI requests are forwarded directly to the AI provider you chose.

What are the charges and pricing rules?

The extension is free, with no ads and no subscription fee. New installs may include promotional free trial credits; beyond those credits you use your own API key, and usage fees are billed by your own AI service provider under its own pricing. Lumen AI does not charge you.

Which AI models are supported?

The extension connects to major AI providers through your own API key, so the models available depend on the provider and key you configure. This bring your own api key extension lets you choose the provider that fits your work.

How do I use the keyboard shortcut?

Open your browser's extension shortcuts page (chrome://extensions/shortcuts in Chrome, or the extensions page in Edge) and assign a shortcut to open the Lumen AI side panel. You can also open the sidebar from the extension icon or right-click menu.

Legal

Privacy Policy & Terms of Service

Privacy Policy

Lumen AI is a browser sidebar extension for Chrome and Edge. It has no backend server. We do not collect your chat content, browsing history, web page content or notes. Your AI API key is stored locally in your browser and is never uploaded to a server of ours. AI requests are sent directly to the AI service provider you selected. The extension shows no ads and does not use analytics or tracking. For support or privacy questions, use the Contact Us link in the footer.

Privacy Policy

Terms of Service

The extension is provided free of charge, with no subscription and no account required. You are responsible for obtaining and configuring your own AI API key, and for any fees charged by your chosen AI service provider except usage covered by promotional free trial credits. Offer terms are shown inside the extension. Lumen AI is a client-side tool only; it does not provide AI services itself and does not resell API access. Install the extension only from the official Chrome Web Store or Microsoft Edge Add-ons store.

Terms of Service