You can read Frequently Asked Questions about UTAU on this page.
Here is a translated version of UTAU’s Software Usage Policy. In the case of anything legal, please refer to the original Japanese text (which can be found in the readme.txt in your UTAU installation).
UTAU is shareware – the program is free to download, but you can pay ¥3562 (or about $33 USD) if you want to support the developer. The paid version of UTAU, according to this forum post, gives you an Automatic VCV tool, the ability to see waveforms, and multi-thread rendering.
If you like UTAU, consider supporting Ameya with the paid version! (Japanese site)
Yes. Always consult them before creating an original or cover with an UTAU voicebank. Usually these cover whether you can use the voicebank in explicit content, and if you can use the voicebank and/or character commercially. Here is an example of an UTAU’s TOS on the UTAU wiki.
Maybe? UTAU voicebanks are generally not sold as standalones, so in the least it is highly discouraged to sell an UTAU voicebank by itself by the community, if not forbidden. However, some voicebanks are sold as part of a larger package, like the Macne voicebanks, which were created as voicebanks for Garageband and Reason, and later releases of Macne voicebanks included configuration for UTAU.
But regardless, if you want to sell an UTAU voicebank that you created (obviously it’s illegal to sell a voicebank that you don’t have the rights to), selling it as part of a package or in addition to a product is accepted by the community and seemingly allowed. For example, you could sell keychains or an album of original songs sung by your UTAU (amongst other things…) and include a code or files to download the UTAU as a bonus.
Almost all UTAUs are 100% free to download, so deciding to sell your bank is a pretty uncommon choice unless you’re part of a company or you’re a voice actor or something. People like free things!
In Japanese, 歌う (うたう/utau) means “to sing”, making it a fitting name for a signing synthesizer. Both the program and the voicebanks can be referred to as “UTAU”.
YES. Otherwise UTAU’s core features will not work. The only reason why you would install UTAU without it is installing it on a work or family computer. If you have a fairly strong computer, but can’t install Japanese locale because it is a shared computer, you could run UTAU in a Virtual Machine.
That’s my UTAU. I thought it would be fun to add them in the logo 🙂
Sorry, I only have a Windows machine, so I can’t help with UTAU-Synth (the Mac version of UTAU) related questions. Most of the main features of UTAU should carry over to UTAU-Synth, and anytime a tutorial mentions Ctrl, substitute it with Cmd. UTAU-Synth supports multi-track .USTs, which Windows UTAU does not.
