Unfortunately, no single metric can provide a definitive answer to the reputation of a journal. The easiest option is you can find the impact factor of a journal on its website or by searching for it on the web. It will be useful to check the editorial board. A reputable journal should have a distinguished editorial board comprising recognized experts in the field. You can check the names and affiliations of the editorial board members on the journal's website.
Well, in the end, ask people's opinions on forums and social networks. You should not trust the reviews found on special sites, most of them are written to order.
