Inbox Zero is an AI executive assistant layered on top of Gmail and Outlook, built by developer Elie Steinbock (elie2222) and one of the most-starred open-source email projects on GitHub. Once you connect a Google or Microsoft account, it sorts incoming mail into smart categories such as To Reply, Newsletter, Marketing, Calendar, Cold Email and Notification, so you can triage by intent instead of scrolling chronologically. Every message that needs an answer arrives with a pre-written draft based on your past writing and your calendar availability, which you edit and send from the same view.
The tool is unusually broad for an email assistant. It blocks cold outreach before it reaches your inbox, shows you which senders you never open and lets you bulk-unsubscribe and archive them in a few clicks, and produces email analytics about who emails you most and what is clogging your inbox. Because it is open source and self-hostable, developers can inspect the code or run it on their own infrastructure — the company is SOC 2 Type 2 compliant and states your data is never used for AI training.
Inbox Zero also ships a dedicated email app for Gmail and Outlook across web, macOS, Windows and iPhone, is designed to be used from Slack, Telegram or Microsoft Teams, and offers AI meeting notes and pre-meeting briefings on higher tiers. The core app is free; the AI features are billed as a per-user subscription add-on.
