How to Use Prompt Weights In Midjourney

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:

  1. 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)
  2. 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
  3. 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 ::
  4. You can also add a negative image weight such as ::-1 (Midjourney will try to eliminate whatever you weigh negatively)
  5. The --no command is the same thing as assigning a section a weight of ::-0.5
  6. 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.

PromptImageComments
wood::teapot --seed 1If you don’t specify a weight after the ::, it is just 1
wood::2 teapot::1 --seed 1Pretty 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 1More wood than teapot
wood::4 teapot::1 --seed 1I guess that’s a handle
wood::5 teapot::1 --seed 1Yep 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:

PromptImageComments
wood::teapot --seed 1Same starting point
wood::1 teapot::2 --seed 1
wood::1 teapot::3 --seed 1Slowly getting rid of wood
wood::1 teapot::4 --seed 1
wood::1 teapot::5 --seed 1More 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:

PromptImageComments
studio ghibli anime, stormtrooper --seed 2963267901(no negative weights added yet)
studio ghibli anime, stormtrooper::1 3d render realistic::-0.1 --seed 2963267901Add 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 2963267901A 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 2963267901More of the same
studio ghibli anime, stormtrooper::1 3d render realistic::-1 --seed 2963267901Interesting

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.

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