If you want an online service to master your music tracks automatically to pro quality, Songmastr is a good choice. The AI-based service lets you upload a song and a reference track, then applies mastering settings based on the reference track. It accepts WAV and MP3 files, and you can master up to 7 tracks per week for free without signing up. Songmastr is fast, cheap and lets you keep full rights to the files you upload.
Another option is the Diktatorial Suite, geared for audio pros and musicians. It offers instant mastering with text prompts to produce hi-fi quality audio and also can be set to optimize for streaming services like Spotify and Apple Music. The suite offers a range of sounds for different styles and has advanced options like stereo width and analog warmth. It also has secure and safe processing, with unlimited revisions.
For a more extensive audio processing experience, check out Cryo Mix. The service offers mastering tools, but also mixing and AI-based audio separation tools. It lets you set parameters for dynamics and EQ to ensure industry-standard quality. The interface is designed to be easy to use, so anyone can create high-quality audio regardless of their skill level.