Wikipedia:Archive your sources
 | This is an essay on preventing and repairing dead links. It contains the advice or opinions of one or more Wikipedia contributors. This page is not an encyclopedia article, nor is it one of Wikipedia's policies or guidelines, as it has not been thoroughly vetted by the community. Some essays represent widespread norms; others only represent minority viewpoints. |
 | This page in a nutshell: It is generally good practice to add archive links to any sources that you introduce to an article. |
You should literally always archive your sources. Yes, even you.
Link rot is a serious problem. No matter how stable or dependable a source seems to be, any source can go down on any day for any reason. A natural disaster could happen, servers could fail, or the site could fall victim to just plain old corporate mismanagement. You'll never know, so archive your sources.
Some tips:
- Make friends with the InternetArchiveBot. It is best practice, in general, to run the bot on whatever page(s) you have edited immediately after you've made any edit to any page that added or changed a non-trivial amount of online sourcing, hell, after adding any online sourcing at all. Once you're reasonably sure that you're done adding sources for the time being, run the bot. This is the absolute minimum of effort you should invest in archiving.
- However, the archive bot obviously won't catch everything. Sometimes the bot's just stubborn and refuses to add a Wayback link. Some sites can't be captured by the Wayback Machine, either because the site's been blacklisted or because archives of the site just won't work for whatever technical reason. In that case, you may need to do it manually. Follow the instructions at Help:Archiving a source. If the source can be archived on the Wayback Machine and the bot just missed it, add the Wayback link. If the Wayback Machine throws you an error, try using archive.today, which will capture almost anything that the Wayback Machine struggles with.
- The Wayback Machine is vulnerable to lawsuits, DDoS attacks, and movements to change legislation in the United States (where it is located) which could potentially make it illegal or difficult to access. While it is under no immediate existential threat as of this writing, having a contingency is not a bad idea. While you're archiving your source on the Wayback Machine, you might want to also archive it to archive.today, and/or some other web archive(s), just to make sure there's an backup. This should be considered especially important if the source in question is the primary or sole source of important information about a topic.
You have no excuse to not do any of this. You may think you don't need to today, but you might just find out that you wished you did tomorrow. Like much of the routine gnoming on Wikipedia, it might be tedious, it might be annoying, and you might decide you just don't wanna do it (and, y'know what, that's okay). But also, like most maintenance to be done on articles, it is important and necessary, and someone's gotta do it. And if you're the one adding the sources, it may as well be you.
Always archive your sources!