Lumo by Proton – The Privacy-First AI Assistant
Lumo by Proton is a privacy-focused AI assistant designed to integrate artificial intelligence directly into a user’s secure communication workflow. Developed by Proton AG, the Swiss company renowned for its end-to-end encrypted services like Proton Mail and Proton VPN, Lumo applies this same security-first ethos to AI. It launched as a key feature within the Proton ecosystem, aiming to solve the fundamental conflict between AI utility and user privacy.
Lumo is built for the growing number of privacy-conscious individuals and professionals who want to leverage AI without feeding their personal data into models run by large tech companies. It targets journalists, activists, business professionals, and everyday users who handle sensitive information. Its primary value proposition is not being the most powerful AI, but the most private. Lumo AI disrupts the prevailing business model by providing a secure, encrypted, and ad-free environment where user conversations are never used for training, ensuring personal and professional data remains confidential.
Best Use Cases for Lumo by Proton
- Privacy-Conscious Professionals: For a lawyer or executive, Lumo can summarize a long, confidential email thread about a sensitive negotiation directly within Proton Mail. It can then help draft a professional, well-worded reply, all while ensuring the content of the conversation remains encrypted and private.
- Journalists & Researchers: A journalist investigating a sensitive topic can use Lumo AI as a research assistant to ask questions, organize notes, and brainstorm ideas. They can do this with the confidence that their query history is not being tracked or used to build a profile on them, protecting both their work and their sources.
- Everyday Proton Users: For the average user looking to improve their daily communications, Lumo by Proton acts as a smart editor. It can take a hastily written draft and instantly correct grammar, improve the tone to sound more professional or friendly, and shorten it for clarity, making every email sent from Proton Mail more effective.
- Small Business Owners: A business owner can use Lumo to draft sensitive internal memos, customer service replies, or even initial proposals. By keeping these communications within the secure Proton ecosystem, they can leverage the power of AI to boost productivity without risking the exposure of confidential business or client information.
Our Expert Rating
Pricing
Starts at: $10/month
Model: Pay per Month
Unmatched Privacy Protections: All interactions are protected by Proton's end-to-end encryption and zero-access architecture. Your data is not used for training models.
Seamless Proton Ecosystem Integration: Works directly within Proton Mail, Calendar, and Drive, providing AI assistance where you need it most.
Trusted Developer: Built by Proton AG, a company with a long and proven track record of fighting for user privacy.
No Ads or Data Monetization: The business model is based on subscriptions, not on selling user data, ensuring your information remains yours.
Practical AI Features: The email summarization and composition tools are genuinely useful and solve common, everyday problems.
Simple and Intuitive Interface: It's a clean, straightforward chatbot that requires no technical skill to use.
Not the Most Powerful AI Model: Lumo's reasoning and creative generation capabilities are not as advanced as other leading models.
Limited to the Proton Ecosystem: It is not a standalone tool and can only be used by subscribers to specific Proton plans.
Lacks Advanced Multimodality: It is a text-based tool and does not offer image, audio, or video generation capabilities.
- AI Chat: A secure, private chatbot for asking questions, brainstorming, and getting information without being tracked.
- Email Summarization: Intelligently condenses long email threads within Proton Mail into concise, easy-to-read summaries.
- Email Composition & Editing: Helps users write new emails from scratch, reply to existing ones, and improve the tone or clarity of their drafts.
- Privacy-First Architecture: Ensures user queries and conversations are not saved or used to train AI models.
- Proton Ecosystem Integration: The core feature that allows Lumo AI to interact with content inside Proton’s suite of applications.
- Web Search: Access to live web search for up-to-date information
- Uploading documents: You can upload documents in diverse format from the Proton Drive or directly from your computer.
Lumo by Proton Interface
Frequently Asked Questions
1. What is Lumo by Proton?
Lumo by Proton is a privacy-focused AI assistant. It is built directly into the Proton ecosystem (Mail, Calendar, etc.) to help you write, summarize, and get information securely.
2. How is Lumo private?
Lumo is private because it is protected by Proton’s zero-access encryption. This means Proton cannot see your conversations, and your data is never used to train AI models.
3. Is Lumo by Proton free?
Yes, Lumo AI has a free version with limited features, as well as a paid version at EUR10 per month with chat history access, more advanced AI modes and larger context windows for document updates.
4. Is Lumo as smart as ChatGPT?
Lumo by Proton is not as powerful as leading models like ChatGPT or Claude 4 for complex creative or reasoning tasks. Lumo’s primary advantage is its privacy and security, not its raw intelligence.
5. Can Lumo read my emails?
Lumo AI can help you summarize and reply to emails you are actively viewing. However, because of Proton’s zero-access encryption, it cannot “read” your inbox on its own, and the company itself never has access to the content.
Tech Pilot’s Verdict on Lumo by Proton
In an era where using a mainstream AI is an act of data donation, Lumo by Proton represents a fundamentally different philosophy. Its existence is a direct response to the market’s growing unease with how Big Tech handles our information. We’ve seen ChatGPT conversations submitted as court evidence and learned how our queries are used to build detailed user profiles. Lumo’s entire purpose is to be the antithesis of this model.
The platform deliberately trades cutting-edge power for ironclad privacy. Lumo AI is not, and does not pretend to be, the most intelligent AI on the market. It won’t write a screenplay with the nuance of Claude 4 or generate code with the flair of a specialized developer model. But that misses the point. Lumo is more than capable for the 95% of professional tasks it’s designed for: summarizing long reports, drafting clear emails, and organizing ideas. Its true product isn’t just AI assistance; it’s trust.
Its power is unlocked by its deep integration within the Proton ecosystem. Being able to summarize a confidential email thread directly in your inbox, without that data ever leaving a zero-access encrypted environment, is a feature that no other major AI player can credibly offer. It’s a tool built not for casual brainstorming, but for professionals whose data is their most valuable—or vulnerable—asset.
Top Alternatives to Lumo by Proton
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ChatGPT / Google Gemini: These are the performance champions. They are vastly more powerful, creative, and multimodal. They are the correct choice for any non-sensitive task where maximum capability is required, but they operate on a model of data collection and user profiling.
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Brave Leo: Lumo’s closest philosophical competitor. Leo is a privacy-first AI built into the Brave browser, making it ideal for anonymizing web queries and summarizing public web pages. Lumo is superior for tasks related to personal and professional communications that live within your email and cloud storage.
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DuckDuckGo AI Chat: The best option for truly anonymous, one-off questions. It acts as a private proxy to models like GPT and Claude, stripping identifying information from your queries. However, it has no memory or integration, making it unsuitable for ongoing, context-aware work.
Final Verdict on Lumo’s Review
Lumo by Proton is not for everyone, and that is its greatest strength. It is built for a specific, and growing, audience that understands that the cost of “free” AI is their personal data. For journalists, lawyers, executives, and any individual who believes in digital privacy, Lumo AI is not just a good choice—it is arguably the only logical one. It has chosen to be the safest AI assistant on the market, and in that, it succeeds completely.