The hardest way to check for broken links is to click on them and see what happens. I’ll do exactly that on occasion, but only when I’m verifying what my broken link checker is telling me. No piece of software is perfect and that goes for broken link checking software as well.
Xenu Link Sleuth has been around for years, as long as I can remember. The latest stable version was released in 2010, five years ago.
Not everyone can use it. Xenu Link Sleuth only runs on Microsoft Windows. If you’re using Linux or OS X as your operating system, you may be able to use it with an emulator but I can’t guarantee it.
I block the Xenu Link Sleuth user agent on any website I have control of, for anyone but me. It operates so quickly that it can seem like a denial of service attack. If it’s used on a website without a good caching system in place (for PHP-driven websites), it can bring that website to its knees.
There’s probably more than one but the one I know about is Check My Links. There’s a built-in disadvantage to using a Chrome extension. You can only check one page at a time.
Unlike Xenu Link Sleuth and the tool I’ll mention next, the Chrome extensions can’t crawl a website. That requires a program or a complex script and Chrome extensions aren’t designed to be that extensive.
The Broken Link Checker plugin has been around since 2007 and it’s changed hands at least once.
This is what I use, but not in its default configuration. Although I may change some of the options from time to time, I won’t let it check links more than once a week (every seven days).
Even though it seems like the plugin is constantly being updated, it isn’t. And even though it does a good job, it isn’t perfect. An example is dismissed links. Sometimes they’ll “undismiss” themselves.
The plugin takes a bit of getting used to, but it works better than anything else I’ve ever used for WordPress. I’m still using it, on my WordPress Static Site Generator (on my PC). Some sites used to forbid it when it came from the server and now they don’t. Some still do, but I think it’s because I’m in the Philippines, which they’ve blocked for whatever reason.
You can get away with having a couple of broken links on a website. Sometimes the websites being pointed to are temporarily down for some reason.
A well-maintained website is a website a visitor may want to return to. If your visitors click on links and they always seem to be broken links, they’ll stop returning.
I’ve been told Google’s search engine will penalize websites with a lot of broken links but I can’t confirm that. Good links benefit your visitors and that’s the reason you should clean up any broken links.
You can try the Screaming Frog SEO Spider Tool, which can be installed on PC, Mac, Linux. I’ve never tested it but I think I need to block it for everyone but me.
You can try the Online Broken Link Checker. I tested it and it works for me.