OpenUTAU

OpenUtau is an open source editing environment for UTAU community with modern user experience.

Main features:

• Navigate the interface naturally and fluently using the mouse and scroll wheel. Keyboard shortcuts are also available.
• Easily create songs and covers using the feature-rich MIDI editor.
• Create expressive vibratos with the easy-to-use vibrato editor.
• Pre-rendering and built-in resamplers let you quickly preview your work.

All features:

• Modern user experience.
• Easy navigation using the mouse and keyboard.
• Feature-rich MIDI editor.
• Support for importing VSQX (Vocaloid 4) tracks.
• Selective backward compatibility with UTAU.
• OpenUtau aims to solve problems with fewer steps. It is not designed to replicate UTAU features exactly.
• Extensible real-time phonetic editing.
• Includes phonemizers for different phonetic systems (VCV, CVVC, Arpasing, etc.) in many different languages (English, Japanese, Chinese, Korean, Russian and more).
• Expressions replace the standard UTAU "flags" for tuning.
• The built-in WORLDLINE-R resampler supports curve tuning, similar to many vocal synth editors.
• Internationalisation, including UI translation and file system encoding support.
• Unlike UTAU, there is no need to change your system locale to use OpenUtau.
• Smooth preview/rendering experience.
• Pre-rendering allows OpenUtau to render vocals before playback, saving time during editing and tuning.
• Supports ENUNU AI singers. See the ENUNU wiki page for more info.
• Easy-to-use plugin system.
• Versatile resampling engine interface.
• Compatible with most UTAU resamplers.
• Runs on Windows (32/64 bit), macOS, and Linux.

What it doesn't do:

• While OpenUtau can do very minimal mixing, it will not replace your digital audio workstation of choice.
• OpenUtau does not aim for Vocaloid compatibility, except for some limited features.