Are free web hosts reliable?

Generally no, although there are a few exceptions. If the free host is making money from banner ads or other revenue sources directly from the free hosting service, then they likely will stay in business, provided someone doesn't abuse their web hosting server with spam, hacking, etc., as often happens to new free web hosting companies with liberal signup policies. If the freehost accepts just anyone, especially with an automated instant activation and it offers features such as PHP or CGI, then some users invariably try to find ways to abuse it, which can cause the free server to have a lot of downtime or the free web server to be slow. It is best if you choose a very selective free hoster which only accepts quality sites (assuming you have one).

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