Question: how to create ringtone for iphone online?
Answer: Open mp3cut.net in your browser.
Choose a file that you want to make into a ringtone. ... 
Select the interval you would like to use by moving the blue markers.
If you would like your ringtone to fade on start and gradually become louder, enable the function "Fade in".
Select the format: iPhone ringtone.
Click "Cut"