Hi! There's some of my favorite converting methods/tools. You can compare the outcomes by making a copy of the original file, trying the methods on the copies, and see what of the following suits you the best for your project:
1- Good old renaming; select your JPG file, and edit the name by adding '.png' at the end, like this: exampleimage.png. It will warn you something catastrophical may happen to the file, but don't worry; generally this only happens if you try to convert a file to an obscure file type or attempt an uncompatible conversion (such as trying to turn a .pdf into a .odt document: no this doesn't work). In image files, the process between jpg-png is safe and even reversible. Still, if your file is unreplaceable, like a photo of yours, you may want to make a copy and do the conversion on the copy.
2- Online alternative; Cloud Convert (cloudconvert ending in .com) Safe and same quality as input file. If file name changing doesn't yield the same quality as original (sometimes happens), this might do. (
Disclaimer: I only reccomend it from experience, I don't work in the service nor I get any benefit from reccomending it, I scanned the website with virustotal and deemed safe, so I use it
)
Hope this helps! I'm also curious about other methods, I'm looking forward to hear more from other users!
