MTA-STS Policy Checker & TLS Validator
Audit RFC 8461 SMTP MTA-STS DNS records and well-known policy files to prevent downgrade and man-in-the-middle attacks on inbound mail transport. 100% free, instant execution, dark mode supported, and zero registration required on TempoMailUSA.
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Overview & Usage
MTA-STS Policy Checker & TLS Validator is a free online tool designed for mta-sts policy validator and generator. Audit RFC 8461 SMTP MTA-STS DNS records and well-known policy files to prevent downgrade and man-in-the-middle attacks on inbound mail transport. It runs quickly and privately in your browser with instant copy and export options.
This tool runs with complete privacy in your browser. All inputs, calculations, and DNS verifications follow current web standards.
Technical Specifications
| Tool Name | MTA-STS Policy Checker & TLS Validator |
|---|---|
| Category | Email & SMTP Forensics |
| Processing | Live Network Lookup |
| Privacy | Private — No inputs are saved or tracked |
| Output Formats | Clipboard Copy, Text, and JSON |
How to Use MTA-STS Policy Checker & TLS Validator
Enter your domain, IP address, text, or code into the input field above, or click one of the quick sample presets.
Click the button to query the network in real time and retrieve up-to-date DNS and protocol records.
Inspect the generated code, formatted results, and diagnostic details in the results panel.
Click the Copy button to copy the output directly to your clipboard, or download it to your computer.