You might’ve seen numbers like ‘::
2′ inside Midjourney prompts. These are called prompt weights, and they help you emphasize (and de-emphasize) certain parts of prompts.
Let’s go through some weighing basics:
- All words have a default weight of 1 (but words at the start of a prompt have a greater effect on the result than words at the end)
- Commas are soft breaks,
::
are hard breaks. This affects how hard MJ tries to turn multiple words into single concepts. So a comma divider says “these are different concepts” and a ‘::
‘ divider says “listen up these are different concepts”. Think of everything between a break as a concept cluster; it does not have to make grammatical sense - PROMPT WEIGHTS: You can use
::
by itself, or you can add a number after it, making something like:::2
or::10
. This will add emphasis to the entire section preceding the::
- You can also add a negative image weight such as
::-1
(Midjourney will try to eliminate whatever you weigh negatively) - The
--no
command is the same thing as assigning a section a weight of::-0.5
- IMAGE WEIGHTS: You can weigh image prompts with
--iw
. More on this below
Seems like a lot to remember, but it’s actually pretty intuitive. Let’s wheel out the examples.
Prompt | Image | Comments |
wood::teapot --seed 1 | ![]() | If you don’t specify a weight after the :: , it is just 1 |
wood::2 teapot::1 --seed 1 | ![]() | Pretty big change I don’t actually have to include the ::1 after teapot because the default weight is 1. I’m including it just for clarity. |
wood::3 teapot::1 --seed 1 | ![]() | More wood than teapot |
wood::4 teapot::1 --seed 1 | ![]() | I guess that’s a handle |
wood::5 teapot::1 --seed 1 | ![]() | Yep that’s wood |
(I’m controlling the seed, because that will give me consistent results where I can compare the effects of changing the weights only)
Let’s go the other way:
Prompt | Image | Comments |
wood::teapot --seed 1 | ![]() | Same starting point |
wood::1 teapot::2 --seed 1 | ![]() | |
wood::1 teapot::3 --seed 1 | ![]() | Slowly getting rid of wood |
wood::1 teapot::4 --seed 1 | ![]() | |
wood::1 teapot::5 --seed 1 | ![]() | More of the same |
Relative weights matter, not absolute
Weights matter in proportion to each other.
So wood::4 teapot::1
will yield the same result as wood::8 teapot::2
which yields the same result at wood::16 teapot::4
and so on.
There’s no need to make the weights very high. I’ve noticed that once you’re going beyond ratios like 1:6
, 1:8
the underemphasized element stops mattering anyways.
Negative weights
Let’s see what happens when you specify what we don’t want with a negative weight:
Prompt | Image | Comments |
studio ghibli anime, stormtrooper --seed 2963267901 | ![]() | (no negative weights added yet) |
studio ghibli anime, stormtrooper::1 3d render realistic::-0.1 --seed 2963267901 | ![]() | Add the negative weight “3d render realistic” because I don’t want the image to be 3D or realistic |
studio ghibli anime, stormtrooper::1 3d render realistic::-0.2 --seed 2963267901 | ![]() | A little negative prompt goes a long way |
studio ghibli anime, stormtrooper::1 3d render realistic::-0.3 --seed 2963267901 | ![]() | |
studio ghibli anime, stormtrooper::1 3d render realistic::-0.5 --seed 2963267901 | ![]() | More of the same |
studio ghibli anime, stormtrooper::1 3d render realistic::-1 --seed 2963267901 | ![]() | Interesting |
Remember that negative prompts also work relatively, so wood::1 teapot::-1
is the same as wood::10 teapot::-10
.
Note: If you are trying to generate anime styles you should 100% use Niji Mode.
‘–no’ command shortcut
The no command is just a shorthand for “::-0.5
” which is just a regular negative weight. I don’t actually use it because I prefer to have more fine-tune control over my weights.
You can use it if you prefer not to deal with the numbers. -0.5
is a pretty good benchmark to zap out anything you don’t want.