Router Checker

Testing for signs of DNS hijacking

Router Checker is a free web-based tool you can use to check your device's connection to its DNS resolver, to make sure it is connecting to an authorized DNS server. A mismatch between the two may indicate DNS hijacking is underway.

To find out more about DNS hijacking and use the Router Checker tool, go to:

Router Checker

Giving Feedback

We would appreciate your feedback on this service! Please send your comments via e-mail to:

Legacy Tool: DNSChecker

The old DNSCheck tool created in response to the 2011 DNSChanger botnet takedown remains available on the Labs Legacy Tools FTP server. The DNSCheck tool checks the PC's DNS settings for potentially malicious changes made by the DNSChanger malware. It can also be used to reset problematic DNS settings.

To use DNSChecker:

Note: This is an F-Secure Labs support tool. It is provided 'as is' without warranty or product support.


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For documentation and product support, visit our Support site.

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For certain cases, a legacy removal tool may be necessary. Legacy tools are stored on our FTP.

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