Email Warmup

Gradually build your email reputation by warming up your sending domain. Our automated warmup process safely increases sending volume to improve deliverability.

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What is Email Warmup?

Email warmup is the process of gradually increasing your email sending volume to build a positive sender reputation with inbox providers (Gmail, Outlook, Yahoo, etc.). When you start with a new domain or IP address, inbox providers are cautious and may filter your emails as spam. Warmup helps establish trust.

The warmup process involves sending a low volume of emails initially (typically 5-10 per day) and gradually increasing the volume over 2-4 weeks until you reach your target sending volume. This mimics natural sending behavior and signals to inbox providers that you're a legitimate sender.

How Our Warmup Works

Automated Volume Ramping

Our warmup algorithm automatically increases your daily sending volume using an exponential growth curve. Starting at 5 emails per day, we gradually ramp up to your target volume (typically 100 emails/day) over approximately 2-3 weeks.

Natural Email Content

We generate natural-looking emails with varied subjects and content to simulate real business communication. This includes follow-ups, questions, and casual messages that appear authentic to spam filters.

Engagement Signals

Emails are sent to our network of seed accounts, and we encourage manual engagement (opens, replies) to build positive signals. High engagement rates tell inbox providers that recipients want your emails.

Reputation Monitoring

We continuously monitor bounce rates, spam complaints, and blocklist status. If we detect reputation issues, the warmup automatically pauses or reduces volume to protect your sender reputation.

Warmup Best Practices

  • Start Slow: Begin with 5-10 emails per day and increase gradually. Rapid volume increases trigger spam filters.
  • Be Patient: Warmup takes 2-4 weeks minimum. Rushing the process can harm your reputation permanently.
  • Maintain Consistency: Send emails every day during warmup. Irregular sending patterns raise red flags.
  • Monitor Metrics: Watch your bounce rate (<2%), spam rate (<0.1%), and engagement rates. Poor metrics indicate problems.
  • Authenticate First: Ensure SPF, DKIM, and DMARC are properly configured before starting warmup.
  • Use Real Engagement: Manual opens and replies are more valuable than automated engagement for building reputation.

When to Use Warmup

  • New Domain: Any newly registered domain needs warmup before sending marketing emails.
  • New IP Address: If you switch to a new dedicated IP for sending, warmup is essential.
  • After Long Inactivity: If you haven't sent emails in 3+ months, consider a brief warmup period.
  • After Reputation Damage: If your domain was blocklisted or had high spam rates, warmup helps rebuild trust.
  • Before Marketing Campaigns: Warm up before launching major email campaigns to ensure deliverability.

Understanding Warmup Metrics

Daily Volume

The number of emails sent per day. This starts low (5-10) and increases gradually to your target volume (typically 50-200 emails/day depending on your needs).

Open Rate

Percentage of warmup emails that are opened. Good warmup should maintain 40%+ open rates. Low open rates may indicate deliverability problems.

Reply Rate

Percentage of warmup emails that receive replies. This is the strongest engagement signal. Target 10%+ reply rates for optimal reputation building.

Bounce Rate

Percentage of emails that bounce. Hard bounces (>2%) indicate problems with your email list or sending infrastructure. Our system monitors this closely.

Spam Rate

Percentage of recipients marking emails as spam. Any spam rate above 0.1% is concerning. Above 0.3% will pause the warmup automatically.

Common Warmup Mistakes

Increasing Volume Too Quickly

Many senders try to reach full volume in days instead of weeks. This is the #1 cause of warmup failure. Inbox providers flag sudden volume spikes as suspicious. Always follow a gradual ramp-up schedule.

Skipping Authentication

Starting warmup without proper SPF, DKIM, and DMARC configuration wastes time and can harm your reputation. Always authenticate your domain first using our validation tools.

Ignoring Bounce Rates

Sending to invalid or inactive addresses during warmup damages your reputation quickly. Our system uses verified seed accounts, but if you see bounce rates above 2%, pause and investigate immediately.

Inconsistent Sending

Sending emails sporadically (some days yes, some days no) during warmup confuses inbox providers and reduces effectiveness. Our automated system ensures consistent daily sending.

Technical Details

How We Send Warmup Emails

Our warmup service sends emails FROM your email address using YOUR SMTP credentials. This is critical - we warm up YOUR domain's reputation, not ours. The emails are sent to our network of verified seed accounts.

From: your-account@yourdomain.com
To: seed-account@inboxreadycheck.com
Authentication: Uses YOUR SMTP server
Result: Builds reputation for YOUR domain

Volume Calculation Algorithm

We use an exponential growth algorithm with a configurable increase rate (default 15% per day):

Day 1: 5 emails
Day 2: 6 emails (5 × 1.15)
Day 3: 7 emails (6 × 1.15)
Day 5: 10 emails
Day 10: 20 emails
Day 15: 41 emails
Day 20: 82 emails
Day 23: 100 emails (target reached)

Automatic Reputation Protection

Our system monitors your warmup continuously and automatically adjusts:

  • If bounce rate > 10%: Reduce volume by 70%
  • If bounce rate > 5%: Reduce volume by 50%
  • If spam rate > 0.5%: Pause warmup immediately
  • If spam rate > 0.3%: Reduce volume by 50%
  • If blocklisted: Pause warmup immediately

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