The DoH/DoT Server Checker is a comprehensive diagnostic tool that tests the availability and performance of DNS servers using encrypted protocols. Here's how it operates:

• Enter the DNS server address (IPv4 or IPv6) you want to test
• Select between DoH (DNS over HTTPS) or DoT (DNS over TLS) protocol
• The tool establishes a secure connection to the specified server
• Performs DNS resolution queries through the encrypted channel
• Measures response times and connection stability
• Displays detailed results including latency, success rates, and configuration status

The checker validates that your DNS infrastructure is properly configured for secure communications and identifies any potential connectivity issues.

Network Administration

System administrators can verify that corporate DNS servers support encrypted protocols and meet security compliance requirements. This ensures all DNS queries remain private and protected from interception.

Privacy Verification

Users concerned about privacy can confirm their DNS provider actually supports DoH/DoT endpoints and measure the performance impact of using encrypted DNS.

Network Troubleshooting

IT professionals can diagnose connectivity issues with DNS servers, identify configuration problems, and optimize network performance by comparing multiple server endpoints.

Security Auditing

Security teams can audit DNS infrastructure to ensure encrypted DNS protocols are properly implemented and functioning correctly across all endpoints.

Performance Optimization

Network engineers can benchmark different DoH/DoT servers to select the fastest and most reliable options for their organization or personal use.

DNS over HTTPS (DoH)

DoH encrypts DNS queries using the HTTPS protocol (TLS 1.2+), allowing DNS resolution to be indistinguishable from regular web traffic. The tool tests DoH endpoints typically on port 443, supporting both GET and POST query methods. This provides excellent privacy and compatibility with most firewalls.

DNS over TLS (DoT)

DoT encrypts DNS traffic using TLS at the transport layer, operating on port 853. The tool verifies TLS certificate validity, cipher suite strength, and successful connection establishment. DoT provides a dedicated encrypted channel specifically for DNS traffic.

Performance Metrics

• Response Time: Measures latency from query initiation to response receipt
• Success Rate: Percentage of successful DNS resolutions without timeouts or errors
• Connection Stability: Tests multiple queries to assess consistency and reliability
• TLS Version: Identifies the TLS protocol version being used
• Certificate Chain: Validates certificate authenticity and expiration status

Supported Features

• IPv4 and IPv6 address testing
• Custom port configuration
• Multiple DNS query types (A, AAAA, MX, TXT)
• Timeout and retry configuration
• Detailed error reporting and diagnostics
• Batch testing of multiple servers

• Enhanced Privacy: Verify that DNS queries are encrypted end-to-end, preventing ISP monitoring and tracking
• Comprehensive Testing: Test both DoH and DoT protocols with a single tool for complete coverage
• Performance Analysis: Identify the fastest and most reliable encrypted DNS servers for your location
• Security Validation: Confirm proper TLS implementation and certificate validity
• Network Optimization: Compare multiple servers to select the best option for your needs
• Compliance Verification: Ensure your DNS infrastructure meets security and privacy standards
• Real-time Diagnostics: Quickly identify and troubleshoot DNS connectivity issues

Regular Testing Schedule

Perform periodic checks on your DNS servers to ensure consistent availability and performance. Monitor for any degradation or changes in response times over time.

Compare Multiple Servers

Test various DoH/DoT providers to identify which offers the best combination of speed, reliability, and privacy for your specific geographic location and network conditions.

Monitor Certificate Expiration

Keep track of TLS certificate expiration dates on your DNS servers. The tool alerts you to certificates nearing expiration so you can plan renewals in advance.

Test from Multiple Locations

If possible, run tests from different geographic locations and network conditions to get a comprehensive view of server performance and accessibility.

Document Baseline Metrics

Establish baseline performance metrics for your DNS servers. This allows you to quickly identify when performance degrades or issues arise.

Verify Configuration Changes

After implementing DNS infrastructure changes, use this tool to verify that encrypted DNS protocols are still functioning correctly.