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Infrastructure

SMTP Checker

Test and validate SMTP servers individually or in bulk before using them in campaigns.

SMTP Checker preview

SMTP Checker

Bulk import, proxies, and advanced checks.

Ready

Server Import

Upload lists, import from DB, or paste manually.

CSV/TXT • host:port:email:password

Select and import stored accounts.

Rage Mode

600 threads • may cause instability

Advanced SMTP Thread & Timeout Settings

Based on 0 servers with 25 threads

1100
5100
10m2h

Paste from Clipboard or Enter Manually

What it does

SMTP Checker validates your SMTP servers to ensure they're working before you rely on them. Test individual servers or run bulk validation across your entire inventory.

What it tests

  • Connection: Can we connect to the server?
  • Authentication: Are the credentials valid?
  • Send capability: Can it actually send mail?
  • Inbox placement: Does mail reach the inbox?
  • Response time: How fast is the server?

Check configuration

  • Set timeouts and concurrency for fast, safe bulk checks
  • Enable optional geo and blacklist signals for deeper screening
  • Route checks through proxies when needed (environment-dependent)
  • Run inbox placement tests to classify inbox vs spam outcomes
  • Promote working accounts into your main SMTP inventory after checks

Operational options

  • Tag results so you can segment working vs risky inventory
  • Auto-quarantine failing accounts to protect ongoing campaigns (where enabled)
  • Schedule recurring checks to keep your pool healthy over time
  • Use Activity Logs to understand why failures cluster after changes

How to use it

  • Test new SMTP accounts before adding to your pool
  • Run periodic health checks on existing servers
  • Bulk validate after configuration changes
  • Identify and remove problematic servers quickly

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