ChatGPT for Outlook vs Inbox Zero

ChatGPT for Outlook is a free Outlook add-in from Blueberry Consultants that runs OpenAI's ChatGPT on messages in your inbox or while you compose new mail. You install it with a manifest URL, connect your own ChatGPT API key, and write custom prompts to summarize threads, pull out key details, or reshape email text without leaving Outlook.

The add-in is built for people who already rely on ChatGPT and want that workflow inside email. You can process a full message or narrow the scope to the body, subject, or attachments, then view results in a separate window or replace the original content. Multiple prompt configurations let you match different inbox scenarios.

Blueberry also offers custom branded versions for teams and resellers, with prompts and API keys tailored to a Microsoft 365 domain. The product is not affiliated with OpenAI or Microsoft, though Blueberry is a Microsoft Partner.

Inbox Zero connects to Gmail or Outlook and uses AI to label incoming mail, draft replies in your voice, and surface what needs attention first. You get pre-written responses waiting when you open your inbox, plus bulk unsubscribe tools for newsletters you never read. The product works on web, iOS, Android, Slack, and Telegram so you can triage mail without living in your email tab.

Most email assistants stop at summarization. Inbox Zero also blocks cold emails, files attachments automatically on higher tiers, and pulls calendar and CRM context into drafts so scheduling replies match your real availability. The codebase is open source with 9k GitHub stars, SOC 2 Type 2 certification, and a self-host option for teams that want full control.

Starter plans cover solo operators who want labels, analytics, and reply drafts. Plus adds Slack, Notion, Stripe integrations, and an unlimited knowledge base. Professional adds team analytics and dedicated onboarding. Over 20,000 professionals use Inbox Zero, and every paid plan includes a 7-day free trial.