> ## Documentation Index
> Fetch the complete documentation index at: https://evolink.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.
# Midjourney V8.1 Prompt Parameter Guide
> All available parameters for the Midjourney V8.1 model in prompts, including value ranges, defaults, dependencies, and conflicts
## 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](#speed-modes) and [Output Quality](#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
```text Correct theme={null}
a yellow Persian cat --ar 1:2 --s 500
```
```text Incorrect theme={null}
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.