Inbox Zero
Open-source AI email assistant for Gmail
About Inbox Zero
Inbox Zero is an open-source, AI-powered email management tool that automates inbox triage with natural-language rules, bulk unsubscribe, cold-email blocking, and a 'Reply Zero' workflow that surfaces only emails actually needing a response. Built primarily for Gmail and Google Workspace.
Pros & Cons
Pros
- Open source — the only credible self-hostable alternative to SaneBox
- AI rules are genuinely powerful and easier to write than Gmail's filter syntax
- Reply Zero is a unique workflow no other competitor offers in this form
- Cold email blocker catches what Gmail's spam filter misses
Cons
- Gmail/Google Workspace only — no Outlook support yet
- Requires technical comfort to self-host (Postgres, OAuth setup)
- Younger product — fewer years of refinement than SaneBox or Mailstrom
Key Features
AI Personal Assistant
Define plain-English rules ('archive all receipts, label as Finance') and the AI applies them.
Reply Zero
Filters the inbox down to only emails awaiting your reply, with AI-drafted responses.
Bulk Unsubscribe
One-click unsubscribe from any newsletter, with sender-block fallback.
Cold Email Blocker
AI auto-detects and archives unsolicited cold sales emails.
Analytics
Tracks who emails you most, your response time, and inbox load over time.
Self-Hostable
Open source (AGPL) — run it on your own infrastructure for full data control.
Pricing
- Self-hosted
- All features
- Bring your own LLM API key
- Cloud-hosted
- AI assistant
- Bulk unsubscribe
- Reply Zero
- Everything in Basic
- Higher AI limits
- Priority support
- Cold email blocker
Best For
Privacy-First Inbox AI
Self-host with your own OpenAI/Anthropic key so no third party ever sees your email.
Founders Drowning in Cold Outreach
Cold email blocker plus Reply Zero filters hundreds of pitches down to actual customer mail.
Power Users Outgrowing Gmail Filters
Replace dozens of brittle Gmail filters with a handful of plain-English AI rules.
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