ConvertKit (now Kit) is an email-first platform that automates email marketing, newsletter growth, and digital product sales for creators.
Free·from $33/mo
About Warmbox.ai
What is Warmbox.ai?
Warmbox.ai is an email warm-up tool that prevents cold emails from landing in spam. By simulating natural email activity—sending, opening, replying, and removing from spam—it builds sender reputation with providers like Gmail, Outlook, Yahoo, and custom SMTP. The result: higher inbox placement rates for outreach campaigns.
Who is it for?
It is ideal for sales teams, marketers, and founders sending cold emails at scale who struggle with deliverability. It is less suited for casual personal email senders with low volume needs.
Real use cases
Sales teams use Warmbox.ai to warm up new domains before outreach. Marketers integrate it with tools like Mailchimp and HubSpot to maintain reputation during campaigns. Founders rely on its private inboxes network of +35,000 accounts to accelerate warming across multiple email providers.
Key features
- Automated Warm-Up — Sends and replies to emails from your address to build reputation
- Multi-Provider Support — Works with Gmail, Outlook, Yahoo, iCloud, Amazon SES, SMTP, and more
- Realistic AI Interactions — Uses GPT-4 to generate human-like emails, replies, and spam removal
- Deliverability Monitoring — Dashboard shows inbox placement rate, spam score, and bounce rate
- Customizable Schedules — Set daily send limits and choose growth, flat, or random warm-up patterns
- Private Inboxes Network — Access to +35,000 inboxes to boost reputation safely
- Live Email Checker — DNS and blacklist monitoring for your domain
