BYOAIK (Bring Your Own AI Key) is a directory of AI tools that run on your own API key.

Zero (Mail0)

Open-source AI email client whose writing and triage features run on the OpenAI key in your own deployment.

Website Source code

Category:
Productivity Tools
Maintenance:
Actively developed (last commit 13 days ago)
Pricing:
Open Source
Open source:
Yes (MIT)
Self-hostable:
Yes
Local-first:
No
Platforms:
Web, Self-hosted, Docker
AI providers (bring your own key):
OpenAI
API key storage:
User controls deployment
Key risk level:
LOW
Trust score:
77/100

Zero is an open-source email client offering a unified inbox across providers together with AI features for composing, summarising and triaging mail. The repository's .env.example lists OPENAI_API_KEY along with model selection variables, so an operator running their own instance supplies their own key rather than routing through a Zero-owned key or subscription. Self-hosted as a standard Next.js deployment. MIT licensed, 10,766 stars, last pushed about two and a half months before review. The project states it does not track, collect or sell email data.

How this tool was scored

Key handling 80/100 (where your key rests and who sees it, comparable across any licence) and verifiability 90/100 (how much of that BYOAIK could confirm, lower for closed source). Neither contains a popularity signal.

  • Key Safety 21/25: The key lives in a deployment you run yourself.
  • Request Routing 17/20: Requests go straight from you to the AI provider.
  • Transparency 20/20: Source is public under MIT, so anyone can check how the key is handled. Key handling was located in the published source.
  • Privacy 10/15: Can be self-hosted, so the data path stays inside infrastructure you control.
  • Maintenance 2/10: Last commit was about 13 months ago.
  • Verification Confidence 7/10: Key handling was found in the published source by BYOAIK's scanner.

What was checked

Verification tier SOURCE_VERIFIED, derived from the evidence below and not set by hand.

  • [STRONG · SOURCE_SCAN] The user supplies their own OpenAI key: the project references its API key variable. source
  • [STRONG · SOURCE_SCAN] The user supplies their own Perplexity key: the project references its API key variable. source
  • [CONFIRMED · SOURCE_SCAN] Most recent commit 2025-08-31, about 13 month(s) ago. source

How your API key is handled

You self-host the app, so your API key lives in your own deployment. Requests are sent directly to the AI provider. Because it can be self-hosted, your key never has to touch a third-party backend.

Setup

Deploy it (Docker/compose), add your provider API key in the admin or environment config, then select models.