Great question — answering as the UphillTech team:
You might want to see this post: How can I tell if a site is Legal? It lists legal sites for streaming anime and reading/buying manga. Is anime1.com legal? Nope. An immediate indicator that a site is illegal is if it's laced with ads that are usually irrelevant to anime/manga in general. anime1.com's anime pages are almost filled up with ads and clicking on anime episode links results to pop-ups. 'You can also check the site information to confirm if they have a valid certificate and connection type,' as mentioned by @Rumplestiltskin. If a green padlock is present, that site is most likely secure and a 'Connection is secure' message will pop out whenever you click on it. This helps you...
Full answer by W. Are: https://anime.stackexchange.com/a/49879 (CC BY-SA 4.0).
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