All too often, we humans mistype a URL or cut and paste a link while missing a character from the original address. Since those URLs usually hide in anchor text and are not visible, these mistakes could go unnoticed for days, months or even years. You can't count on visitors to report invalid URL: fixing your problems is not part of their job. Of course, URLs don't fix themselves (yet.) Regardless, Google and other search engines don't particularily appreciate invalid, missing or dead links. The engines end up penalizing the authors and their sites for those simple mistakes.
Sneaky errors such as those are one more reason why you should always perform a thorough QA review of anything that you're about to publish. Luckily, there are tools to help you avoid such mistakes. They are called Link Checkers and they've been around for almost as long as URLs exist.
When it comes to validating on-page anchors, LinkMiner is a fine-looking weapon for your Quality Assurance (QA) arsenal. It does exactly what it promises to do. LinkMiner is an eye-pleasing and straightforward Chrome extension that validates all the links present in a given page. Simply click on the extension's icon and you'll get near instant feedback, good or bad.
Let's get this straight: LinkMiner is meant for ad hoc, one-page-at-a-time QA reviews. If you need to perform a site-wide audit, you are probably much better off using more generic tools. Such tools come with most integrated SEO suites, such as Moz, AHref and countless others. The latter provide a full range of services related to bulk-checking your links, and the results will be just as accurate -- and, as we'll see, often more actionable. On the other hand, firing up a site-wide crawler is an overkill solution when it comes to performing a quick audit before publishing a resource.
The extension will quickly scan the page and report back on the errors is finds. For example, we reviewed the LinkMiner homepage, and it displayed the following status pop-up:
From the status pop-up, users can download the results in a spreadsheet by clicking on the down-arrow button, or configure and fine-tune the extension itself by clicking on the cog wheel.
There are a few features we'd like to see in any on-page link validation tool, and those are missing from LinkMiner.
No quick locater -- It would be useful to be able to jump to the anchors that were identified as errors. Those get highlighted in red in the page, but you still need to scroll through the entire page to find them visually. There's no way to quickly jump to the next error from the status pop-up.
Confusing queues -- The queued validations are often the most problematic ones. They usually occur when an invalid is used in an anchor. Because the tool cannot proceed to resolve the URL, it puts in a so-called "queue." Since there's no flag specific to invalid URLs and they don't count as "errors,", those incomplete links are left hanging and are not highlighted. To resolve them, the user has to refer to the downloaded spreadsheet, then locate the improperly formatted link in the source to fix the issues. This is not the most useful or intuitive solution to a relatively common problem. Here's an example from the same report:
Strict social media checks -- Until you configure the tool to use a commercial API using a key (which are technically free, with some limitations), LinkMiner will report and highlight errors on all links that use one of the leading social media back-ends (Twitter, Facebook, etc.). This occurs even if the link themselves are perfectly fine. Configuring the tool to use the API, but it is an extra step that you don't necessarily want to take.
The tool looks good and works really quickly. However, because it is meant as an ad hoc tool for on-page reviews, it should at least address the first two issues and provide a way to identify and locate real errors faster.