Loudness Penalty is a new plugin from MeterPlugs that lets you see exactly how much your music will be attenuated – i.e. how much its volume will be affected – across various streaming services such as Spotify and YouTube. The plugin lets you essentially preview the loudness of each platform in your DAW, rather than waiting until the music has been distributed. You could essentially master a different version to maximise sound quality across each service.
Most streaming services feature a combination of compression and limiting in order to create a consistent listening experience for their users, meaning that your music could be negatively affected if it crosses a certain threshold. However, the threshold changes depending on the service, so this plugin is designed to give you the best shot at the highest quality sound. It's currently $29 for a limited time, rising to $49. Get it here.
If you're interested in getting your tracks on Spotify but don't have the budget, SoundCloud recently announced their new service to distribute your music to major streaming platforms for free, provided you're a Premium customer.