Microsoft SNDS vs Unspam.email
Microsoft SNDS
substrate.office.com
Unspam.email
unspam.emailSide by side
| Figure | Microsoft SNDS | Unspam.email |
|---|---|---|
| Price from | Free | $5/mo |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | Yes |
| API | — | Yes |
| Plans published | 1 | 7 |
| Spec score · Email Deliverability Software | 7.2 (#27) | 8.5 (#7) |
| Intended users | Microsoft describes SNDS as a service for senders and ISPs managing email deliverability and sending reputation for Outlook.com consumers. | The company describes the platform as serving marketers, founders, agencies, and product teams. |
| Purpose | SNDS provides data to help senders understand and improve their reputation at Outlook.com. | Unspam is an email deliverability platform that checks spam signals, sender authentication, blacklists, previews, heatmaps, and inbox placement. |
| Support | For urgent Outlook.com delivery issues, Microsoft advises contacting sender support with someone familiar with the issue and email infrastructure. | The company lists support chat and [email protected] for support or product inquiries. |
Plans
Unspam.email
- FreeFree
- No accountFree
- Custom plan$5 a month
- Basic$9 a month
- Business$19 a month
- Agency$29 a month
- White LabelPriced on request
In their own words
Microsoft SNDS
Microsoft SNDS has no write-up on Specifiction yet; its figures are above.
Unspam.email
Unspam.email is an email deliverability platform for examining spam signals, sender authentication, blacklists, previews, and inbox placement. Spam tests assess authentication, sender reputation, blacklists, and message content, then show which checks affected the score. Inbox placement tests send a campaign to seed mailboxes at Gmail, Outlook, Yahoo, and other providers and report where it landed. Email previews cover rendering across more than 50 real clients and devices in light and dark modes. Scheduled tests can track placement and spam scores and send alerts by email when results decline. Its API has 39 endpoints across seven areas and can test mail sent through SES, Postmark, SendGrid, Mailgun, or a sender’s own SMTP setup; an MCP server lets compatible AI clients run tests and retrieve results. The free plan includes 21 tests per month, unlimited sender accounts, and 14-day data retention, but excludes DMARC monitoring and full API access. Custom costs $5 a month, with a $5 monthly minimum and pay-per-test rates.