Virustotall

If you search on Google "scan files online", you'll find some. But there is no reason not to use virustotal.

The only reason I wouldn't use virus total is if I had something that I didn't want every security analyst in the world to know about.

I heard that VirusTotal sends an extra copy of the stub to antivirus analysts to figure out what is going on. Not confirmed though. I personally used to use VirusTotal back in 2010 and will continue doing so.

you can check it with virustotal then other sites too.
nothing wrong with checking files on multiple sites

you can use Hybrid Analysis too, is a good virus scan.

I always recommend VirusTotal. They basically scan the file you uploaded to dozens of great anti-viruses so you can get a good answer of whether that file is safe or not.

Virustotal not nessecarily better than others but it gets the job done and was originally

It is simple and practical I think, there is even a software

I think it's the only one on the webwhichserve scanning with biggest database of viruses.