CFG SCALE STABLE DIFFUSION

Last updated: June 19, 2025, 19:24 | Written by: Dan Larimer

Have you ever wondered how to make your AI-generated images *exactly* what you envisioned?In the fascinating world of Stable Diffusion, a single setting holds the key to unlocking the full potential of your text prompts: the CFG scale. 在使用Stable Diffusion web UI、ComfyUI等进行生图的时候，提示词引导系数 (CFG Scale) 是常用设置参数之一，那么你了解过CFG Scale是什么吗？今天就代大家了解一下CFG Scale，让大家以后在SD生图的时候更容易设置该参数。提示词引导系数 (CFG Scale)有什么作用？Short for Classifier-Free Guidance scale, this parameter acts as a guiding force, dictating how closely the AI should adhere to your instructions during the image generation process. CFG Scale可以从0-30进行调整，从日常的出图过程经验来看，CFG设置为5-15之间是最常规以及最保险的数值。过低的CFG会让出图饱和度偏低，过高的CFG则会出现粗矿的线条或过度锐化的图像，甚至于画面出现严重的崩坏。Think of it as a volume knob for your creative vision, allowing you to fine-tune the balance between strict adherence to your prompt and the AI's own artistic interpretation.But mastering the CFG scale isn't just about cranking it up to the maximum.It's about understanding its nuances, its relationship with other settings, and how it interacts with different Stable Diffusion models.This guide will delve deep into the concept of CFG scale, exploring its impact on image quality, how to use it effectively, and providing practical tips to achieve the perfect balance for your artistic endeavors.Get ready to take control and transform your text prompts into stunning visual realities!

What is CFG Scale?

The CFG scale, or Classifier-Free Guidance scale, is a crucial parameter in Stable Diffusion that controls the influence of your text prompt on the generated image.It essentially tells the AI how much weight to give your words when creating a visual representation. The higher the number, the more you want it to do what you tell it. The lower the number, the more you're okay with it not following your prompt closely.A lower CFG scale allows the AI to be more creative and deviate from the prompt, while a higher CFG scale forces the AI to stick more closely to the provided description.

In simpler terms, it's like telling an artist how much freedom they have when painting a picture based on your description. Understanding the CFG scale in Stable Diffusion. Learning how to use it to enhance image quality in our blog. Introduction. The CFG scale, also known as the Classifier Free Guidance scale, plays a crucial role in controlling the adherence of Stable Diffusion to your text prompt, which can be used in both text-to-image (txt2img) and image-to-image (img2img) generations.Do you want them to follow your instructions precisely, or do you want to give them some room for improvisation? 【CFGスケール】とは？ CFGスケールは、Stable Diffusionにおける重要な設定の一つです。これは「Classifier Free Guidance」の略で、AIが生成する画像がどれだけ入力されたプロンプトに忠実になるかを調整するために使用されます。The CFG scale is your way of communicating this to the AI.

How CFG Scale Affects Image Generation

The CFG scale has a profound impact on the final output of your Stable Diffusion generations. CFG（Classifier-Free Guidance）用于控制Stable Diffusion在采样期间应遵循提示词的严格程度。几乎所有稳定扩散 AI 图像生成器都提供了此参数设置。今天我们重点来看看在Stable Diffusion中CFG参数相关内容。一. CFG是什么. 我们先以一个实例来看看CFG在不同参数值时的效果。Understanding these effects is crucial for achieving the desired results.

Low CFG Scale (e.g., 2-6):
- Allows for greater creativity and artistic freedom.
- Can result in images that are loosely based on the prompt or even deviate significantly.
- Useful for abstract or experimental art where precise adherence to the prompt is not necessary.
- May produce images with lower saturation or a ""washed out"" look.
Medium CFG Scale (e.g., 7-10):
- Strikes a balance between prompt adherence and artistic freedom.
- Generally recommended for most prompts and provides a good starting point for experimentation.
- Produces images that are recognizable and related to the prompt while still allowing for some variation.
High CFG Scale (e.g., 11-15+):
- Forces the AI to strictly follow the prompt.
- Can result in more detailed and accurate images, but may also lead to artifacts or over-sharpening.
- Useful for complex prompts or when you need the image to closely match your specific vision.
- Can sometimes lead to image degradation or unnatural results if pushed too high.

It's important to note that the optimal CFG scale can vary depending on the complexity of the prompt, the specific Stable Diffusion model being used, and your desired artistic style. CFG scale is a parameter that controls how strict the AI should follow the prompt in image generation. Learn how to choose the best CFG scale value according to the complexity of the prompt words and see the effect of different CFG scale on the same prompt.Experimentation is key to finding the sweet spot.

Finding the Right CFG Scale for Your Prompts

Choosing the right CFG scale is not an exact science, but here are some general guidelines to help you get started:

Start with the default. Most Stable Diffusion interfaces default to a CFG scale of around 7-8.This is a good starting point for most prompts.
Consider the prompt complexity. Simpler prompts may benefit from a lower CFG scale to allow for more creativity.More complex prompts may require a higher CFG scale to ensure the AI captures all the details.
Think about your artistic goals. Do you want a photorealistic image that closely matches your description, or are you aiming for a more stylized or abstract result?Adjust the CFG scale accordingly.
Experiment! The best way to learn is by trying different values and observing the results.Generate several images with varying CFG scales and compare the differences.
Pay attention to artifacts. If you notice strange artifacts, over-sharpening, or image degradation, try lowering the CFG scale.

Don't be afraid to deviate from the recommended ranges.Sometimes, unexpected results can lead to exciting discoveries.

CFG Scale and Negative Prompts

Negative prompts are a powerful tool for refining your Stable Diffusion generations by telling the AI what *not* to include in the image. By tuning both Distilled CFG (how the rehearsal unfolds) and CFG Scale (how the final show is performed), you craft the perfect duet of literal adherence to your prompt and imaginative flair. It s a dance between letting your prompt truly shine and letting the model s creativity riff making each image generation a unique show that sThe CFG scale interacts with negative prompts in interesting ways.

Generally, a higher CFG scale will also increase the influence of your negative prompt, meaning the AI will be more likely to avoid the elements you've specified.However, some experimentation is needed to find the optimal balance.You might find that a lower CFG scale with a strong negative prompt produces better results than a high CFG scale with a weak negative prompt.

It's also worth noting that some users have found that negative prompting techniques work well across different CFG levels, suggesting that the impact of CFG on negative prompt fixation might be limited. Pero para usar la escala de manera m s efectiva, puede seguir la demostraci n a continuaci n sobre c mo usarla en Stable Diffusion. Parte 2. C mo usar la escala CFG en difusi n estable. En esta demostraci n, puede comenzar a experimentar con CFG en DreamStudio o Playground. Sin embargo, hay m s opciones disponibles para usted, como laMore research and experimentation are ongoing in this area.

CFG Scale and Sampler Steps

The number of sampler steps is another important setting in Stable Diffusion that affects the quality and detail of the generated image.It determines how many times the AI refines the image during the diffusion process.

Generally, a higher number of sampler steps will result in a more detailed and refined image.However, increasing the sampler steps also increases the processing time. Most of what I generate for fun benefits a ton from high steps high CFG. Like a potato with eyes for eyes. Nightmare fuel that needed both a high CFG and lots of steps to resolve. If all you want is pretty people or oil paintings sure CFG 7 or RNG luck works fine.The CFG scale and sampler steps are interconnected.If you are using a low CFG scale you may want to increase your sampling steps to add more definition to the generated image.

It is often recommended that images generated with higher CFG scales should also use higher sampling steps to resolve the detail requested in the prompt.

There's no single ""magic number"" for sampler steps, but a range of 20-50 is often recommended. 如果 CFG Scale设置为 -1，则忽略该提示。你有同等的机会产生一只猫、一只狗和一个人。如果 CFG Scale设置为中等 (7-10)，则遵循提示。你总是会生成一只猫。如果CFG Scale设置为高等（大于10以上）可以获得更明确的猫图像. Classifier-free guidance.无分类器指导。五.Experimentation is key to finding the optimal balance between quality and speed.

CFG Scale and Different Stable Diffusion Models

Different Stable Diffusion models can respond differently to the CFG scale. What is the CFG Scale in Stable Diffusion? CFG stands for Classifier-Free Guidance and the corresponding CFG scale serves as a guiding force during the image generation process in Stable Diffusion. It essentially controls the balance between: Fidelity to the input text prompt. Creativity infused into the final output imageWhat works well for one model may not work as well for another.

For example, some older models may struggle with high CFG scales, leading to more artifacts and image degradation.Newer models, on the other hand, may be able to handle higher CFG scales without any issues.

It's important to familiarize yourself with the specific characteristics of the model you're using and adjust the CFG scale accordingly.Researching the model's documentation or online forums can provide valuable insights.

Distilled CFG: A Nuanced Approach

Beyond the standard CFG scale, some advanced techniques, such as Distilled CFG, offer even finer control over the image generation process.Distilled CFG essentially allows you to control how the ""rehearsal"" (or initial stages) of image generation unfolds, complementing the standard CFG scale, which governs how the ""final show"" (or the final image) is presented.

Think of it as fine-tuning both the underlying process and the final presentation to achieve the perfect balance between adherence to your prompt and the AI's creative flair. The Classifier-Free Guidance (CFG) scale controls how closely a prompt should be followed during sampling in Stable Diffusion. It is a setting available in nearly all Stable Diffusion AI image generators. This post will teach you everything about the CFG scale in Stable Diffusion.By adjusting both Distilled CFG and the standard CFG scale, you can create truly unique and personalized images.

Dynamic Thresholding (CFG Scale Fix)

One of the challenges with using a high CFG scale is that it can sometimes lead to image artifacts or degradation. I would say that my experiment supports this novel style of negative prompting at all CFG levels, though it doesn't look like CFG impacts the fixation on the negative prompt to a useful degree. Further experimentation is warranted. Experiment 3 - CFG scaleTo address this, some Stable Diffusion implementations offer a feature called Dynamic Thresholding (CFG Scale Fix).

This feature dynamically adjusts the threshold used during the diffusion process, allowing you to use higher CFG scales without sacrificing image quality. The Guidance Scale, also known as the Classifier-Free Guidance (CFG) scale, controls how closely Stable Diffusion adheres to the provided text prompt during the image generation process. In other words, it determines the extent to which the generated image reflects the input text.It essentially helps to prevent the AI from over-interpreting the prompt and introducing unwanted artifacts.

If you're consistently using high CFG scales and encountering issues with image quality, Dynamic Thresholding may be a valuable tool to explore.

Practical Examples of CFG Scale in Action

Let's look at some practical examples to illustrate the effects of different CFG scale values:

Example 1: ""A cat sitting on a windowsill""

CFG Scale 2: The image might be very abstract and barely resemble a cat or a windowsill.The colors may be muted, and the composition may be unconventional.
CFG Scale 7: The image will likely show a recognizable cat sitting on a windowsill. CFG scale is crucial in adjusting image similarity to prompt and/or input. Understanding the concept of CFG scale and its impact on stable diffusion is essential for achieving high-fidelity output images. The Concept of CFG Scale. In stable diffusion, the CFG scale refers to a parameter that influences the image generation process.The details will be reasonably accurate, and the overall composition will be pleasing.
CFG Scale 12: The image will be very detailed and realistic.The cat's fur will be rendered in great detail, and the windowsill will be accurately depicted.However, the image may also appear somewhat artificial or over-sharpened.

Example 2: ""A futuristic cityscape at night""

CFG Scale 4: The image might be a blurry, abstract representation of a city at night. 以上でCFG Scaleについて解説しました。 CFG Scaleは最適な数値に設定することで、イメージに沿った画像生成をすることができるので時間短縮につながります。 CFG Scaleのおすすめ設定値は「6〜14」になります。The colors may be vibrant, but the overall composition may be chaotic.
CFG Scale 8: The image will show a recognizable futuristic cityscape with skyscrapers, flying cars, and neon lights.The details will be reasonably accurate, and the overall composition will be dynamic.
CFG Scale 14: The image will be incredibly detailed and realistic.The skyscrapers will be intricately designed, the flying cars will be sleek and futuristic, and the neon lights will be vibrant and eye-catching.However, the image may also appear somewhat overwhelming or artificial.

These examples are just a starting point.The actual results will vary depending on the specific prompt, the Stable Diffusion model, and other settings. The classifier-free guidance scale (CFG scale) is a value that controls how much the text prompt steers the diffusion process. The AI image generation is unconditioned (i.e. the prompt is ignored) when the CFG scale is set to 0. A higher CFG scale steers the diffusion towards the prompt. Stable Diffusion v1.5 vs v2But they illustrate the general trend of how the CFG scale affects the image generation process.

Common Questions About CFG Scale

What does CFG stand for?

CFG stands for Classifier-Free Guidance.

What is the recommended CFG scale value?

A CFG scale of 7-10 is generally recommended as a good starting point for most prompts. So when to use different CFG scale values? CFG scale can be separated into different ranges, each suitable for a different prompt type and goal. CFG 2 6: Creative, but might be too distorted and not follow the prompt. Can be fun and useful for short prompts; CFG 7 10: Recommended for most prompts. Good balance between creativity andHowever, the optimal value can vary depending on the prompt complexity, the Stable Diffusion model, and your desired artistic style.

Can I use a CFG scale of 0?

Yes, you can use a CFG scale of 0. Le CFG Scale, ou Classifier-Free Guidance Scale, est donc param tre crucial pour exploiter pleinement le potentiel de Stable Diffusion. J esp res qu en vous aidant mieux comprendre son fonctionnement du CFG Scale et son impact sur la g n ration d image, vous pourrez affiner votre utilisation de Stable Diffusion et cr er des imagesIn this case, the AI will ignore the prompt and generate an image based purely on random noise. The guidance scale, also known as the Classifier-Free Guidance (CFG) scale, is a setting within Stable Diffusion that determines how closely the generated image adheres to the text prompt. Essentially, it acts as a control knob that adjusts the level of adherence between the AI-generated image and your written description.This can be useful for creating abstract or experimental art.

What happens if I set the CFG scale too high?

Setting the CFG scale too high can lead to image artifacts, over-sharpening, and image degradation.It can also make the image appear artificial or unnatural.

How does the CFG scale interact with other settings?

The CFG scale interacts with other settings such as the number of sampler steps, the negative prompt, and the Stable Diffusion model.It's important to consider these interactions when fine-tuning your image generation process.

Conclusion: Mastering the CFG Scale for Stunning AI Art

The CFG scale is a powerful tool for controlling the image generation process in Stable Diffusion. See full list on decentralizedcreator.comBy understanding its effects and how it interacts with other settings, you can fine-tune your prompts and achieve stunning results. Dynamic-Thresholding(CFG Scale Fix)とは、CFG Scaleの数字を大きくしても画像を破綻させることなく、綺麗な画像を生成できるStable Diffusionの拡張機能になります。この機能を使用することで、よりプロンプトに忠実で品質が劣らない画像を生成できます。Remember, there's no one-size-fits-all answer to the ""perfect"" CFG scale.Experimentation is key to finding what works best for you and your artistic vision.

Key takeaways:

CFG scale controls the adherence to your prompt.
Lower CFG allows for more creativity, higher CFG enforces strict adherence.
Optimal CFG depends on prompt complexity, model, and desired style.
Experiment with CFG scale, sampler steps, and negative prompts.
Consider using Dynamic Thresholding for high CFG values.

Now that you have a comprehensive understanding of the CFG scale, go forth and create amazing AI art!Don't be afraid to experiment, push the boundaries, and discover new possibilities. Learn how to use CFG scale and distilled CFG to control how closely Stable Diffusion follows your prompt and how much it improvises. See examples, explanations, and tips for different CFG settings and styles.Happy generating!