Checking websites for broken links and invalid email addresses is an indispensable means to ensure a professional website. LinkByLink is a fast, platform-independent link checker which solves these and other tasks. The application, the user's manual and user support are offered in English and in German. The results of a website check executed by LinkByLink can be exported in various file formats and can be filtered using regular expressions. The integrated HTML source code browser helps finding the exact location of an error in the HTML sources. Accessing secure websites is supported by a certificate and authentication manager. The number of parallel connections can be configured. Multi-threading ensures an optimum of performance and makes full use of the power provided by multi-core processors. A more detailed feature list is available on the LinkByLink homepage. LinkByLink is available as Standard Edition and as Pro Edition. The Pro Edition offers numerous additional features. A validating parser is included, which verifies the structure of your HTML. The optional console mode without a graphical user interface is ideal for automated tests. Results can be stored in an SQL database or can automatically be forwarded by email. The HTTP communication can be recorded in order to analyze general communication problems.