10 Best Domain Warming Tools for Founders [2026 Updated]

1. AutoWarmUp

• Type: Free
• URL: https://autowarmup.com
• Overview: AutoWarmUp is an automated email warm-up platform that sends, opens, replies, and moves messages to improve sender reputation using a peer-to-peer warmup network. The service includes deliverability monitoring and supports Gmail, Google Workspace, and custom SMTP/IMAP connections to gradually increase sending volume.

2. Mailwarm (mailwarm.com)

• Type: Paid
• URL: https://www.mailwarm.com
• Overview: Mailwarm automates positive email interactions (opens, replies, marking as important) through a large warmup network to raise your domain and mailbox reputation. It provides a dashboard to control daily warmup intensity and monitor deliverability metrics while scaling warmup activity over weeks.

3. MailWarmup (mailwarmup.ai)

• Type: Paid
• URL: https://mailwarmup.ai
• Overview: MailWarmup.ai is an AI-driven warmup platform that combines a vetted warmup pool with deliverability checks and DNS health monitoring to optimize inbox placement. The tool generates varied, human-like warmup content and tracks sender health while offering customizable warmup sequences.

4. Lemwarm (by lemlist)

• Type: Paid
• URL: https://lemlist.com/lemwarm
• Overview: Lemwarm is lemlist’s built-in warm-up solution that plugs into your mailbox and engages with a vetted network of users to simulate human-like opens and replies to improve deliverability. It also tracks a deliverability score and alerts you to spam risk while scaling sending volume safely.

5. Folderly (Email Warmup Service)

• Type: Paid
• URL: https://folderly.com
• Overview: Folderly offers an AI-powered email warmup service as part of its deliverability platform, gradually increasing send volume and simulating realistic engagement to boost inbox placement. The service includes real-time analytics, blacklist monitoring, and expert deliverability support to fix technical issues and optimize domain health.

6. Warm Up Your Email (WarmUpYour.Email / Mailshake)

• Type: Paid
• URL: https://warmupyour.email
• Overview: Warm Up Your Email provides automated warmup with configurable schedules that open, reply, and remove messages from spam to build sending reputation across providers like Gmail and Outlook. The product includes logs and reports so you can track warmup progress and adjust intensity per mailbox.

7. WarmupInbox

• Type: Paid
• URL: https://warmupinbox.com
• Overview: WarmupInbox runs continuous automated interactions—opens, replies, and folder movements—through a private network of inboxes to improve deliverability for new or inactive domains. Users get a control dashboard to set daily interaction volumes and view inbox placement metrics during the warmup period.

8. Warmbox (warmbox.ai)

• Type: Paid
• URL: https://warmbox.ai
• Overview: Warmbox.ai offers a warmup platform with a large private inbox network, customizable warmup “recipes,” and monitoring tools for DNS, blacklists, and spam score. It emphasizes realistic conversation patterns and adjustable reply/open rates to progressively establish a positive sender reputation.

9. TrulyInbox

• Type: Free
• URL: https://www.trulyinbox.com
• Overview: TrulyInbox automates realistic, human-like warmup interactions by joining your mailbox to a warmup pool of other accounts, performing opens, stars, and replies to raise sender credibility. The platform supports major ESPs and provides a deliverability score and account-level controls for daily warmup limits.

10. Warm Up My Email (WUME / warmupmyemail.com)

• Type: Paid
• URL: https://warmupmyemail.com
• Overview: Warm Up My Email (WUME) sends scheduled warmup emails to a large pool of accounts that manually or automatically open, mark important, and reply to boost mailbox and domain reputation. The service includes a monitoring dashboard and configuration options to control daily interactions and warmup pacing.