Midjourney V8.1 Prompt Parameter Guide

Parameter Overview

Parameter	Syntax	Type	Range	Default	Description
Aspect Ratio	`--ar W:H`	Integer ratio	Any positive integer ratio	1:1	Image aspect ratio
Chaos	`--c N`	int	0 - 100	0	Diversity of generated results
Seed	`--seed N`	int	0 - 4294967295	Random	Fix seed for reproducible results
Stylize	`--s N`	int	0 - 1000	100	Artistic style intensity
Experimental	`--exp N`	int	0 - 100	0	Aesthetic effect, stackable with stylize
Raw Mode	`--raw`	Flag	—	Off	Disable default beautification
Image Weight	`--iw N`	float	0 - 3	1	Image prompt influence
Style Reference	`--sref [URL]`	URL	—	—	Match visual style
Style Weight	`--sw N`	int	0 - 1000	100	Style reference strength
Object Reference	`--oref [URL]`	URL	—	—	Place a character/object into the scene
Object Reference Weight	`--ow N`	int	1 - 1000	100	Object reference strength

Two settings are not written into the prompt — they are controlled through the API instead (writing them in the prompt has no effect):

Speed (draft / fast) → model_params.speed
Output quality (standard / hd) → top-level quality parameter

--v / --version is locked to V8.1 and --niji is not supported. See Speed Modes and Output Quality below.

Basic Parameters

Aspect Ratio `--ar`

Sets the image aspect ratio. Only integer ratios are supported.

a cat --ar 16:9

Common values: 1:1, 4:3, 3:2, 16:9, 9:16, 2:3. Extreme ratios may produce unpredictable results.

Chaos `--chaos` / `--c`

Controls the diversity of generated results. Higher values produce greater differences among the 4 images.

a cat --c 50

Range	Effect
0	4 images are very similar (default)
1-50	Moderate diversity
50-100	Highly random, suitable for creative exploration

Stylize `--stylize` / `--s`

Adjusts the balance between realism and artistic style.

a cat --s 500

Range	Effect
0-250	Realistic style, faithful to the prompt
250-750	Balanced
750-1000	Strong artistic expression, bold colors and composition

Experimental `--exp`

Similar to --stylize but stackable, generating more detailed, dynamic, and creative images.

a cat --exp 25

Recommended values: 5, 10, 25, 50, 100
Noticeable effect changes from 5-50, diminishing returns from 50-100
May override --stylize effects above 25-50

Raw Mode `--raw`

Disables default beautification for stricter adherence to prompt details. Suitable for photorealism or precise control scenarios.

product photo --raw

Seed `--seed`

Fixes the initial random state for comparison testing.

a cat --seed 23453422

Range: 0 - 4294967295
Same seed + same prompt → similar (not identical) results

Image Reference Parameters

Image Prompt

Place image URLs at the beginning of the prompt to influence the generated content.

https://example.com/ref.jpg text description --iw 1.5

Valid combination rules:

Combination	Valid?
1 image + no text	❌ Invalid (will error)
1 image + text description	✅ Valid
2+ images + no text	✅ Valid
2+ images + text description	✅ Valid

Maximum 20 image prompts
Supported formats: .png, .gif, .webp, .jpg, .jpeg
Not available with draft speed (use fast)

Image Weight `--iw`

Controls the influence of image prompts on the result. Range 0 - 3, default 1. Higher values produce results closer to the reference image.

https://example.com/ref.jpg watercolor landscape --iw 2.0

Style Reference `--sref`

Matches the visual style (colors, textures, lighting) of the reference image without copying content. Must be used with a text prompt.

a cat --sref https://example.com/style.jpg

Multiple supported: --sref URL1 URL2
Random style supported: --sref random (returns a numeric code after generation, reusable)
Maximum 20 srefs

Style Weight `--sw`

Controls the influence of the style reference. Range 0 - 1000, default 100.

a cat --sref https://example.com/style.jpg --sw 500

Object Reference `--oref`

Places characters, objects, vehicles, or non-human creatures from the reference image into a new image. Must be used with a text prompt.

a duckling holding a magic wand --oref https://example.com/duck.jpg

Only one object reference image can be used, and generation takes longer when it is active.

Object Reference Weight `--ow`

Range 1 - 1000, default 100. Recommended to keep below 400, otherwise results may be unpredictable. High --stylize values may require higher --ow to compensate.

duckling --oref https://example.com/duck.jpg --ow 300

Speed Modes

Speed mode is controlled via the API’s model_params.speed field (do not write --draft / --fast in the prompt).

Mode	Description	Cost
`draft`	Returns 24 lightweight 0.5K sketch images in a single run. Image generation endpoint only.	Same multiplier as fast
`fast`	Standard mode (default), 4 images per generation	Standard

Unlike V7, V8.1 draft mode is not half price — it uses the same multiplier as fast. Draft returns 24 small sketches in one run; pick the ones you like and re-run them at full quality. Draft cannot be combined with hd quality.

Output Quality

Output resolution is controlled via the top-level quality parameter, not a prompt flag. Do not write --hd in the prompt.

Value	Resolution	Cost
`standard`	Standard resolution (default)	1x
`hd`	Native 2K HD output	1.5x

The quality multiplier is combined (multiplied) with the speed multiplier.
hd is incompatible with draft speed.

Dependencies

The following parameters require other parameters to take effect:

Parameter	Prerequisite
`--sw`	Requires `--sref`
`--ow`	Requires `--oref`
`--iw`	Requires image prompt
`--sref`, `--oref`	Requires text prompt
Single image prompt	Requires text prompt

Conflicts

Parameter A	Parameter B	Description
`draft` speed	`hd` quality	Draft mode cannot be combined with HD
`draft` speed	Image prompt / `--sref` / `--oref`	Image references require `fast`
Image-only prompt	`--stylize` / `--exp`	Incompatible without text
`--exp` > 25	`--stylize`	High `--exp` may suppress `--stylize`; lower `--exp` when combining

Unsupported Parameters in V8.1

Parameter	Description
`--q` / `--quality`	Detail-level flag not exposed on this route (use the top-level `quality` parameter for resolution instead)
`--no`	Negative prompt not exposed on this route
`--weird` / `--w`	Not supported
`--tile`	Not supported
`--sv`	Style version is locked; not exposed
`--stop`	Not supported
`--cref` / `--cw`	Use `--oref` object reference instead
`--relax`	Not supported
`--repeat` / `--r`	Not supported via API
`--p` (personalize)	Not supported via API
`{}` permutations	Not supported via API
`--stealth` / `--public`	Not supported by API (images are not publicly accessible)
`--niji`	A different model, not V8.1
Multi-prompt `::`	Not supported

Prompt Format Guidelines

Basic Structure

[image URL] text description --param1 value1 --param2 value2

Writing Rules

Parameters go at the end of the text prompt
A space is required before --
Do not use punctuation in parameters
No text can follow after parameters

Examples

a yellow Persian cat --ar 1:2 --s 500

a yellow Persian cat--ar 2:3          ← missing space before --
a yellow Persian cat - - ar 2:3       ← space between --
a yellow Persian cat --ar 2:3, --s 50 ← punctuation in parameters
a yellow Persian cat --ar 2:3 more description ← text after parameters

Content Moderation Notice

Midjourney has a built-in content moderation system. If some generated images are filtered by moderation, credits consumed for that request will not be refunded. Please ensure your prompts comply with content guidelines.

Image Series

Video Series

Audio Series

Text Series

Account Management

Task Management

File Management

Midjourney V8.1 Prompt Parameter Guide

Parameter Overview

Basic Parameters

Aspect Ratio `--ar`

Chaos `--chaos` / `--c`

Stylize `--stylize` / `--s`

Experimental `--exp`

Raw Mode `--raw`

Seed `--seed`

Image Reference Parameters

Image Prompt

Image Weight `--iw`

Style Reference `--sref`

Style Weight `--sw`

Object Reference `--oref`

Object Reference Weight `--ow`

Speed Modes

Output Quality

Dependencies

Conflicts

Unsupported Parameters in V8.1

Prompt Format Guidelines

Basic Structure

Writing Rules

Examples

Content Moderation Notice

​Parameter Overview

​Basic Parameters

​Aspect Ratio --ar

​Chaos --chaos / --c

​Stylize --stylize / --s

​Experimental --exp

​Raw Mode --raw

​Seed --seed

​Image Reference Parameters

​Image Prompt

​Image Weight --iw

​Style Reference --sref

​Style Weight --sw

​Object Reference --oref

​Object Reference Weight --ow

​Speed Modes

​Output Quality

​Dependencies

​Conflicts

​Unsupported Parameters in V8.1

​Prompt Format Guidelines

​Basic Structure

​Writing Rules

​Examples

​Content Moderation Notice

Parameter Overview

Basic Parameters

Aspect Ratio `--ar`

Chaos `--chaos` / `--c`

Stylize `--stylize` / `--s`

Experimental `--exp`

Raw Mode `--raw`

Seed `--seed`

Image Reference Parameters

Image Prompt

Image Weight `--iw`

Style Reference `--sref`

Style Weight `--sw`

Object Reference `--oref`

Object Reference Weight `--ow`

Speed Modes

Output Quality

Dependencies

Conflicts

Unsupported Parameters in V8.1

Prompt Format Guidelines

Basic Structure

Writing Rules

Examples

Content Moderation Notice