Below is a list of job plug-ins for VOCALOID™. Each of these plug-ins is designed to enhance the VOCALOID software usage in some way, from minor to major.
This feature of the software was introduced starting from VOCALOID3 and Yamaha also features their own plug-in store, where users of the software can purchase these plug-ins. Plug-ins, however, are not necessarily supported by Yamaha themselves and are maintained by their programmers who made them. With that in mind, it is worth noting that ones in particular that are not made by Yamaha and may not be 100% guaranteed to work with all features of the software, or in fact other plug-ins for the software. Many of the plug-ins developed by the Yamaha Corporation are free, therefore these additional plug-ins are often worth trying out.
Despite their usefulness, a few of the plug-ins may be covered by software DAW or other audio-enhancing software. Therefore, they are not always useful for the specific Producer working with the software, and VOCALOID is perfectly usable without the aid of these plug-ins. Some plug-ins are already included with the VOCALOID3 editor despite appearing in the VOCALOID STORE and therefore are a part of the standard VOCALOID package.
It is not just Yamaha producing plug-ins for VOCALOID3, and there are currently other unofficial plug-ins being produced. Caution may be needed to be expressed with these plug-ins due to being made without Yamaha's consent.
Job Plug-ins are absent as a function in VOCALOID5.
List of Job Plug-ins
Do note that Vocal libraries voicebanks themselves are also counted as a type of Plug-in for the software; however, they are not listed here, as they are listed as "Vocal Library Plug-In" rather than "job plug-in".
Plug-ins which are featured as part of the regular VOCALOID3 software will be listed on the VOCALOID3 page. Some plug-ins are not listed in certain language versions of the VOCALOID STORE, so producers may not be able to purchase these without looking at the specific version to find them.
Many plug-ins are designed to recreate vocal effects without the need of a separate DAW for the same task. This allows VOCALOID to use those effects smoothly within the software.
VocaListener2 was announced in July, 2010. The "2" has since been dropped from the name. VocaListener was the most anticipated of the plug-ins as its existence was known and demonstrated since VOCALOID2.
- Demonstrations of the follow VOCALOIDs: Kagamine Rin(ACT2), Hatsune Miku
- For more details, see Vocaloidism.com
However, despite the hype for its release, one of the problems with this plug-in was noted as its price, with users noting that even discounted at ¥20,000 when it went on sale, it was considered still too expensive. There were alternatives available that were either free or much cheaper, the recorded data also would at times be difficult to edit and remove issues such as background noise. Use of the plug-in was best therefore in a studio set up and not in an amateur one. Thus, very few Japanese producers purchased this plug-in. 
Other issues also included the note you needed a decent vocalist for the app to get good recording results. However, if you owned a decent singer for the app, you also didn't have much use for the app, and perhaps not even a Vocaloid to begin with. Especially as the main purpose of VOCALOID was to provide a "singer in a box" and act as a replacement singer when a decent real one was lacking.
In addition though the original NetVOCALOID vocal support English, this version was only focused on Japanese, limiting its market. Results made for Japanese could face problems when switch the lyrics in favour of those for another language, due to the way pronunciations impact pitching, phonetic glides, etc.
This is a special plug-in only able to be purchased with ZOLA PROJECT. It is designed only to work with their vocals and allows the 3 to sing in unison as a chorus.
Sachiko comes with its own Plug-in called "Sachikobushi". This adjusts VSQx files to make her sing like her provider. While this only works with her software, the created VSQx files can be used on other VOCALOIDs, though the results may not be satisfactory.
This is a plug-in that comes with the Fukase package. "Electronica-Tune" allows a vocal to add distinct pitching effects to the voice such as a robotic sound. The plug-in works with other VOCALOIDs and is a essentially a easy tool to make robotic-like vocals without the troubles caused by drawing the same effect free hand. The result is a voice that sounds "auto-tune" like but does not produce the same results.
Another plug-in by Voctro Labs, this time for English. Designed only for use with MAIKA, it too can be downloaded from their website.
Doubles the duration of all notes and events in the songs. Made by Voctro Labs, this is downloadable from the Voctro-Labs website instead of the Yamaha Shop.