The Deliverability Score
When you run a deliverability test, SendLucid sends a real email through your setup and grades it on 25+ individual checks, rolled up into a single 0–100 score. Each check belongs to one of five categories, and each category carries a different weight toward the total.
The five categories
| Category | Weight | What it covers |
|---|---|---|
| Authentication | 35% | SPF, DKIM, DMARC, BIMI, reverse DNS, MX |
| Blacklists & Reputation | 25% | IP/domain/body-link blacklists, domain age, sender reputation |
| Content & HTML | 20% | Spam words, subject line, links, unsubscribe header, image/text balance |
| Infrastructure | 10% | TLS, HELO match, IP type, domain suffix |
| Best Practices | 10% | Additional sending hygiene (expanding) |
Authentication and reputation dominate on purpose — they’re what mailbox providers weigh most heavily, and they’re where most senders lose placement.
How a check is scored
Every check returns pass, warn, fail, or skip, and contributes points toward its category. Your category scores combine by the weights above into the overall 0–100.
Scores map to a letter grade so you can read them at a glance:
| Grade | Score |
|---|---|
| A+ | 90–100 |
| A | 80–89 |
| B | 70–79 |
| C | 60–69 |
| D | 50–59 |
| F | 0–49 |
Reading your report
Each check on your report explains what it found, why it matters, and how to fix it. Start at the top: a single failed Authentication check usually moves the score more than several small content tweaks. See the Deliverability Checks reference for what each check verifies.