Every time you verify an email with Mailerio, whether through the Dashboard, Bulk Verification, or the API, the system returns detailed results that describe the quality and deliverability of that address.
This guide explains what each status and flag means, how to interpret the score, and how to use these insights to protect your sender reputation and improve deliverability.
Overview
Mailerio analyzes multiple layers of each email address:
- Syntax and format validation
- Domain and MX record checks
- Mailbox and SMTP response analysis
- Provider, role, and disposable detection
- Scoring and risk assessment
The outcome is a status (e.g., deliverable, risky, undeliverable, unknown) plus additional flags such as free, disposable, or role.
Primary Statuses
| Status | Meaning | Action Recommendation |
|---|---|---|
| Deliverable (Valid) | The email address exists, the mailbox is active, and the domain can receive messages. | ✅ Safe to send. |
| Undeliverable (Invalid) | The address does not exist, the domain is invalid, or the server rejected the validation. | ❌ Remove from your list, the email will bounce. |
| Risky | The address exists, but there are risk factors such as a full mailbox, temporary issues, or inconsistent SMTP responses. | The server temporarily rejected the request, but might accept later attempts. |
| Catch-All (Accept-All) | The domain’s mail server accepts all messages, even for non-existent users. | ⚠️ May appear valid but can bounce later. Use carefully. |
| Unknown | The verification could not be completed (e.g., timeouts, greylisted servers, or temporary blocks). | ⏸ No charge for these. Try re-verifying later. |
| Greylisted | The server temporarily rejected the request but might accept later attempts. | 🔄 Wait and retry after a few minutes or hours. |
| Blacklisted | Domain or email appears in your blacklist. | 🚫 Automatically skipped; Mailerio does not verify it. |
| Whitelisted | Domain or email is on your whitelist and automatically marked as “unknown.” | ✅ No verification done (by your choice). |
| Duplicate | The same email was already included in the current batch. | 🌀 Automatically skipped to save credits. |
Additional Flags & Fields
| Field | Description | Usage Example |
|---|---|---|
disposable | true if the address comes from a temporary or disposable provider (e.g., Mailinator, TempMail). | ❌ Block these; they offer no long-term engagement value. |
free | true if the address uses a free provider (e.g., Gmail, Yahoo). | Some businesses prefer to exclude free emails to focus on business domains. |
role | true if the address is generic (e.g., info@, sales@, support@). | ⚠️ Typically shared inboxes; personalization is impossible. |
noReply | true if the address cannot receive responses (e.g., noreply@domain.com). | 🚫 Avoid sending messages expecting engagement. |
mailboxFull | The recipient’s mailbox is full and can’t receive new messages. | ⚠️ Retry later or mark as risky. |
mxRecord | The detected MX record for the domain (mail server). | Useful for diagnosing domain-level issues. |
smtpProvider | Name of the email service provider handling the domain. | Helpful for filtering or analytics. |
tag | Custom identifier passed in the verification request. | Used for mapping results back to your internal system. |
Scoring System
Mailerio assigns every email address a score from 0 to 100, reflecting the overall deliverability confidence.
| Score Range | Meaning | Recommended Action |
|---|---|---|
| 80–100 | Excellent, low risk. | ✅ Safe to send. |
| 60–79 | Moderate risk may include catch-all or older addresses. | ⚠️ Send with caution; monitor engagement. |
| 40–59 | High risk poor SMTP response, or inconsistent data. | ❌ Consider excluding from campaigns. |
| 0–39 | Undeliverable or invalid. | 🚫 Remove from your database. |
Tip: You can use the score as a flexible filter. For example, reject signups with a score below 60, or only send campaigns to addresses above 70.
How to Interpret Results for Your Business
Different businesses have different risk tolerances. Here’s how you might apply Mailerio’s data:
| Goal | Recommended Filters |
|---|---|
| Protect sender reputation | Exclude undeliverable, risky, and unknown. |
| Prevent fake signups | Block disposable and role emails. |
| B2B SaaS targeting | Accept only emails where free = false. |
| Newsletter signups | Allow risky and catch-all with a score above 60. |
| Lead quality enforcement | Combine filters: isValid = true, score ≥ 70, disposable = false, free = false. |
Mailerio doesn’t decide what to block — you do. The system gives you the intelligence; your workflow decides what to allow or reject.
Why These Results Matter
Regularly verifying and interpreting results helps you:
- Keep your sender reputation healthy.
- Avoid hard and soft bounces.
- Increase your email deliverability rate.
- Focus on engaged, valid recipients.
- Improve ROI for marketing and transactional email campaigns.
Sending to invalid or risky emails can quickly lower your domain reputation and land your messages in spam folders.