Full documentation:
https://ghostmade.xyzYou will need to understand a little about how the structure of some files are saved. For instance, SVG's are compressed and saved as a Base64 Encoded variant, so you will need to either decode that file, and reupload, or manually upload the SVG file back to the server with a workflow.
Other than that, make sure to choose your formats correctly, and you will be fine.
Go here to signup and then get a key:
https://www.convertapi.com/a/signupFree users get about 1500 second conversions time then it switches to a monthly model of conversion time.