You can change the key of a song in semitones (half steps) or in cents, which are 1/100th of a semitone, for finer control. You can adjust tempo at the same time as key, then preview your changes before processing and downloading the final file.
You can try it on a free trial basis by signing up for a free account, which lets you process five files at no cost. After that, you can choose from several paid options, including one-time and subscription plans.
Yes. Once you've set your key and tempo adjustments, you can preview the result before processing the file and downloading it to your computer.