---
title: 'BETTER Mouth Tracking in VTube Studio (iPhone 10+ AND Webcam!)'
source: 'https://youtube.com/watch?v=-kTMgYYOuoI'
video_id: '-kTMgYYOuoI'
date: 2026-07-28
duration_sec: 1123
---

# BETTER Mouth Tracking in VTube Studio (iPhone 10+ AND Webcam!)

> Source: [BETTER Mouth Tracking in VTube Studio (iPhone 10+ AND Webcam!)](https://youtube.com/watch?v=-kTMgYYOuoI)

## Summary

This guide by Cozy Chu provides detailed instructions for improving mouth tracking in VTube Studio for both iPhone and webcam users. It covers specific settings adjustments for iPhone tracking, parameter tweaks for mouth movement, and troubleshooting common issues like cheek puff and mouth closure.

### Key Points

- **Introduction to Mouth Tracking Guide** [00:00] — Cozy Chu introduces a remake of their mouth tracking guide, focusing on VTube Studio for 2D avatars using iPhone or webcam.
- **iPhone Tracking Settings** [00:36] — iPhone tracking settings like blink sensitivity and mouth open sensitivity are controlled in the iPhone app, not in VTube Studio. Adjust these first.
- **Auto Setup and Cheek Puff Fix** [02:17] — Start with auto setup. If cheek puff is linked to mouth smile, change input to cheek puff (iPhone only).
- **Mouth Closure Adjustment** [03:33] — To ensure mouth closes completely, set the bottom value of mouth open parameter to a small number like 0.03.
- **Maximizing Mouth Tracking Range** [04:03] — Adjust bottom and top values of mouth smile and mouth open parameters to increase range of motion. Example: bottom 0.3, top 0.8 for mouth smile.
- **Advanced Lip Sync Calibration** [06:28] — Use advanced lip sync to calibrate mouth shapes to your voice by making sounds and adjusting parameters.
- **Mouth X Parameter for iPhone** [10:11] — Mouth X allows side-to-side mouth movement. Set top to 0.3 and bottom to -0.3 for easier activation with small facial movements.
- **Webcam Tracking Setup** [11:42] — For webcam, tracking settings are in VTube Studio. Adjust mouth open sensitivity and other parameters to fix issues like mouth opening too far.
- **Manual vs Automatic Parameter Setup** [15:34] — Switching from automatic to manual parameter setup can help with webcam tracking. Use simple lip sync for better control.
- **iPhone vs Webcam Tracking Comparison** [16:56] — iPhone tracking is generally better than webcam, but webcam can be improved with proper settings. Everyone's face is different, so tweak accordingly.

### Conclusion

By adjusting iPhone app settings and VTube Studio parameters, you can significantly improve mouth tracking. Experiment with values to find what works best for your face and model.

## Transcript

so you want better mouth tracking I can
probably help with that hi what's up I'm
cozy Chu and if you don't know me
already I actually made one of these
guides before but on my main Channel and
now I'm just remaking it uh with a
little bit more depth I wanted to make
sure that there was a guide out there
specifically for mouth tracking and like
changing settings and stuff like that
for both iPhone and webcam keep in mind
that this is something specifically for
vtube studio and it's not for any other
tracking programs and it's not for 3D
and it's only for 2D avatars all right
okay so we're going to start with iPhone
tracking but we're going to start with
something really specific with iPhone
tracking that I don't think a lot of
people talk about and that is the actual
settings on your iPhone for your
tracking so you'll have to go to the app
you'll have to go to this little camera
button here and you'll have to scroll
down to specifically these settings the
blink sensitivity eye open sensitivity
mouth open sensitivity all of this is
controlled specifically by your iPhone
settings it's not controlled in app and
if you change any of these settings on
Steam then it's not actually going to do
anything so you'll have to change if you
want your blink sensitivity to be higher
if you want your eye open sensitivity to
be higher all of this stuff on here is
controlled by your iPhone so make sure
that you make these changes here first
um same thing with if you if you don't
want your eye blinking linked or if you
do want your eye blinking linked or
something like that you have to control
that through here not through the Steam
app there's also a blink fix thing if
you need to mess with that I'm going to
talk about mostly mouth tracking just
make sure that you mess around with your
settings in the iPhone app as well as
your actual vtube studio app sorry if my
tracking is a little wonky it's because
I'm waving my my hand in front of
my
iPhone a lot of those set are really
self-explanatory so I'm not really going
to go over them I have created a
different export of my model that is
specifically for iPhone tracking that
doesn't have any settings on it so I'm
going to start from a completely fresh
State as if I just have uploaded this
model for the first time usually I start
with the auto setup because that's a
good starting place the auto setup sets
things up kind of weirdly sometimes if
we zoom in here you can see there's
something weird going on with my cheek
puff I find this happens every single
time this might not be the case for you
um from a model that you got from a
different rigger just if it does happen
if this is something that's going on for
you make sure you go into your settings
into little person icon at the top
scroll down and try to find where your
cheek puff setting is mine
is down near the
bottom um here we go so it says Pam
cheek and right now it's linked to mouth
smile what you need the the input to be
is instead cheek puff this is an iPhone
only thing so if if you don't have an
iPhone then don't worry about it but
we'll get to that in the actual webcam
part okay so you can turn that on for me
I also need to do something like this to
make sure that it doesn't do a cheek
puff like at the start and
then that's what happens when I like
puff my cheeks out and stuff I'm
actually going to make this like point
or something I don't
know okay so the first problem that I
like to solve after my cheek puff is I
like to make sure that my mouth can
close usually I have a lot of issues
with that because I have really big lips
so I'll go to the mouth open parameter
and I'll go down to the bottom here and
I will make the bottom just something
like
0.03 something really
small so that my mouth closes and make
sure that it completely closes no matter
what so that's my first issue second um
if you watch this red dot on both the
mouth smile and mouth open parameters
you can get an idea of how much you're
getting out of your mouth tracking as
you can see on the mouth form it only
really stays in the middle and then goes
up and then on the mouth open it only
really stays on the bottom and hits the
middle so I'm not getting the most out
of my mouth tracking right now so the
best way to deal with this is
usually to go to this in part
here and if you want to make it so that
it goes lower if you want you know the
the bottom point to actually hit this
bottom here you want to make the bottom
number a little bit bigger so I'm going
to make mine. 3 so that starts
me at a more default expression it
starts me not quite frowning but I can
still like hit a frown point with my
Expressions um but I'm I'm not
constantly smiling and only able to
smile next thing I'll usually do to get
the most out of my my parameters is to
change the top number and I usually
lower this a tiny bit my default is to
go3 on the bottom and 08 on the top and
you can see that offers a pretty large
range of motion depending on whatever
Expressions I'm using and you could see
the Red Dot like really bumping around
all over the place that's what I
like then we can go back to the mouth
open parameter you can see that usually
it's only really close to the bottom and
it only really hits up to about the
middle portion sometimes that's fine
sometimes you don't want your mouth to
open that wide that's okay if you do
want your mouth to open wider then
you're going to want to lower this top
number again I'm going to go for
something just to show you I'm going to
go for something like 7 so so you can
see that it hits the top range of my
possible mouth open a lot quicker and a
lot easier I usually I think for this
model go for about 0.9 so it's a little
bit higher but it's not like super
overboard um and that is the easy way to
set up your mouth tracking parameters as
you could see I already have a much
better mouth tracking um setup there is
one other thing that you can mess with
to try and make this better you can turn
on the advanced lip sync which is using
my voice to try and tart each one of
these shapes um personally I found that
uh if I just calibrate each of these
like letters as I'm making a sound with
the right shaping for my mouth it
usually makes it a little bit more
accurate so for
instance for this is a a o uh are
different sounds that it's working with
so I'll hit
calibrate
ah and I'll try and make the right mouth
shape as I'm trying to do these
different
sounds No that's not quite what I
want I'm not quite hitting it but you
know what I'm kind of going for there
with the with the teeth closed and stuff
then
[Music]
[Laughter]
o
o and then you could do uh silence
calibration too you could just be
like so yeah that ends up calibrating a
little bit better to my voice I found so
it it listens to whatever sounds I'm
making and it tries to set them to the
right mouth parameters there is a way
for a live TD riger to set it up to have
each one of these different parameters
its own thing um and then you you
usually do this setup in model sort of
thing here I've never really done that
so I can't really explain to you how to
do that there may be another video out
there that does I personally have never
really needed it because I usually get
pretty good mouth tracking without that
so I'm not really going to worry about
it this time around uh maybe next time
but this is basically um set up for
iPhone that that's pretty much how I
would deal with my mouse tracking on
iPhone if we pull back up my other
model I
have this one is already set up with all
my tracking how I usually do it you can
kind of see that you can kind of see
that the Mal tracking is about the same
it's a little bit different on this one
but that's just because I I've tweaked
it a little bit more than that the the
settings are slightly different than
they are um in the you know default
setup I I mess with my settings a
lot but it's a lot better than it was
and you could play with the numbers and
you could try and make things you know
closer to however you want them to be
just in case you were curious what my
default settings are for this model
right now um and how I've have tweaked
things uh you can kind of
see it's not quite what I was saying
for the default one that I was making
but it's pretty close um I also
technically changed the uh maximum on my
mouth open um technically it'll say at
the top 1.2 Max that is the total like
Max points of the rigging um you'll
usually want that number to match with
what the actual Max is because that'll
usually help you get the most out of
your tracking um I think on the the
default one that I put in it was it
something like 2.1 so make sure that
that is about uh what the actual Max is
there or if not quite at least pretty
close in number okay and the last face
tracking thing that you'll have to deal
with with an iPhone specifically the
this is something that only iPhones can
do along with like the cheek puff thing
is mouth X you may or may not have this
rigging um just make sure that you know
if you if you want this sort of rigging
if you want the cheek puff if you want
the mouth X you're telling the person
who is doing your rigging um that you
want these features so that they can
make sure that they're in there but uh
mouth X is
basically the side to side motion of
your mouth so um you may need to set up
this parameter in general it might not
even be here um this is on my default
model so I've already set it up and this
is on the iPhone default model um where
it actually already automatically set it
up so that I can
move side to side and stuff but I like
to make it a little bit easier for me to
actually hit the the mouth um X because
I think it's a little bit nicer if I
don't have to like move my face as much
I I make pretty small facial motions
usually so it's a little bit easier if I
set it up to uh account for that so what
I'll usually do is I'll make the top
like3 and the bottom like netive .3 that
keeps it still in the middle but makes
it a lot easier to hit the mouth X
parameter without like straining your
face okay so now we've set up for iPhone
so I'm going to set up for webcam so I'm
going to do the auto setup
again oh my God I look so mad so my
webcam is set up above my uh normal like
PC setup my iPhone is usually set below
so I've got like a a monitor that you
know it it sits up a little bit oh my
God I look so crazy right
now um I usually find that webcam
tracking is better from above and for
some reason iPhone tracking is better
from below I don't know why that is
that's just what I've found uh let me
fix this freaking cheek puff I'm just
going to get rid of it because like I
said that does not work on webcam oh my
God look at how crazy look at how
insane look how actually insane I
look okay so um on set this to 1.2 Max
okay that already helped quite a bit but
um for webcam tracking my mouth actually
opens a little bit too far now keep in
mind when we started iPhone tracking we
uh changed these things here the
tracking settings all of
these have to be set up in vtube studio
when you're doing webcam tracking so for
instance um I think my mouth open
sensitivity might be too high so I'm
going to lower this and as you can see
that actually already helped quite a bit
same with the eye open sensitivity
Ah that's that does help it helps the
blink sensitivity will lower a little
bit too
um I I do look a little bit insane on
this one um and then the mouth smile
sensitivity we can probably lower too um
so I'm going to start with this and then
we will go back here and take a look at
my mouth open settings and stuff like
that this one instead of having a
problem with my mouth not um staying
closed I'm having a problem with my
mouth closing too much so what I'm
actually going to want to do is I think
lower uh this number
so that is an idea of how you can fix
that I'm going to actually make
it1 still not quite
right3 not quite
ne01 not
quite. you really got to play with
things um and and then I'm going to make
the top part let's
go8 or something like that seems a
little bit better same thing with the
mouth smile currently I'm stuck in mouth
smile hell I'm so far up so I'm actually
going to make this like0 five or
something like that instead oh my God
iph iPhone is what I'm used to At This
Point webcam tracking is insane man
there so many problem problems with this
I'm going to have to do a full webcam uh
tracking setup I'm just going to focus
on the mouth for now though I'm also
going to
reset this to default values um just
to actually let me go to simple lip sync
just for a
moment so okay
so my God I'm sorry I'm just I'm
laughing at myself I'm I look so insane
right now I look crazy oh oh my God
webcam is wild okay so just a little bit
of an update I changed a couple of
things um this is my normal model with
webcam tracking as you can see the
webcam is tracking my face and stuff
like that already um these are the
settings that I ended up at and actually
I swapped from automatic to manual which
seemed to help a lot with the parameter
setup that I'm doing on here and then I
am also still using the simple lip sync
right now so let me go ahead and go into
my face settings on here and show you
what I've got for the mouth smile this
is the same as I use my default mouth
open this is the same as I use my
default mouth X I haven't changed
anything in here from like my normal
default stuff um technically I've still
got my like mouth X and stuff but if I
try and wiggle my mouth it doesn't do
anything because I am in I'm completely
in webcam mode now if if I swap from
webcam to normal tracking you can get an
idea of the difference between the two
So currently camera is
on camera is off now I'm back to uh my
iPhone tracking again so that is a
difference it's quite a big difference
but that's a difference between webcam
and iPhone tracking iPhone tracking is
just always going to be better like I
mentioned
um but you can at least set it up to be
better and look a lot more smooth
overall so definitely mess with your
settings if you want to try and copy the
settings that I've got here and see if
that works for you that's fine but make
sure that everyone's face is different
right so you got to make sure you do
edits for yourself I had to do certain
things because things like I have a a
little bit of a lazy eye sometimes I've
got I've got problems with my lips being
too big Etc just make the changes that
you need and keep twe
until it you think it looks good so this
isn't set up for an entire model there
are other things that I like to make
changes on on model setup so I will do
probably a second video for that later
on especially things like uh tweaking
your eye settings so that you smile more
tweaking things like um adding in a Tail
Wag sort of thing stuff like that a lot
of this stuff will be done by your model
Creator before you get the model so you
only only really need to make changes if
this is like your first time ever
setting up a model and you rigged it
yourself or something or um if you are
noticing that you're having a lot of
issues with your face tracking just not
being what you want it to be so just
make sure that you are trying to keep in
contact with your rigger if you're
having any issues with tracking um talk
to them about it as well as trying to
make changes see if there's anything
that they can help you with ask
questions don't ask me questions I don't
know how your model's
rigged so yeah anyway I hope it helps um
see you later byebye