Understand email deliverability scores. Learn what factors affect your score, how to check it before sending, and how to improve inbox placement rates.
A deliverability score is a number (typically 0-100) that predicts how likely your email is to reach the inbox instead of the spam folder. It analyzes your email content, sending infrastructure, and sender reputation.
Most email tools show you open rates and bounce rates after you've already sent. By then, the damage is done — your emails are in spam, your domain reputation is hurt, and your campaign is wasted.
Checking before sending lets you fix problems before they happen.
| Factor | Impact | What to do |
|---|---|---|
| Spam trigger words | High | Avoid "free", "guarantee", "click here" |
| Email length | Medium | Keep 50-150 words for cold email |
| Number of links | High | 0-1 links maximum |
| ALL CAPS words | Medium | Never use all caps |
| Exclamation marks | Low | Maximum 1, preferably 0 |
| Image-to-text ratio | Medium | Plain text is best for cold email |
| HTML complexity | Medium | Simple HTML or plain text only |
| Factor | Impact | What to do |
|---|---|---|
| SPF authentication | Critical | Must pass |
| DKIM signing | Critical | Must pass |
| DMARC policy | High | Set up at minimum p=none |
| Sending domain age | High | Use domains aged 2+ weeks |
| IP reputation | High | Use reputable email providers |
| Sending volume | Medium | Stay below 50/mailbox/day |
HeraMail calculates a 0-100 score on every email before you send it. The score checks:
| Score | Meaning | Action |
|---|---|---|
| 90-100 | Excellent | Send with confidence |
| 70-89 | Good | Review flagged issues |
| 50-69 | Risky | Fix issues before sending |
| 0-49 | Poor | Rewrite the email |
Check your deliverability score before sending — try HeraMail free: heramail.io