What is a negative prompt in AI image generation?

A negative prompt tells an AI image model what to leave out. Where your normal prompt describes what you want to see, the negative prompt lists what you want to avoid — "blurry, extra fingers, watermark, text" — and the model steers away from those things. It is a filter for the stuff you keep getting but never asked for, and it often improves an image more than adding words to the positive prompt does.

Where do you put a negative prompt?

It depends on the tool, but the idea is the same everywhere:

• Stable Diffusion and most web UIs built on it give you a separate negative prompt field right next to the main one. Whatever you type there is treated as "avoid this."
• Midjourney has no separate box; you use the --no parameter at the end of your prompt, as in --no people, text, to exclude those elements.
• Other generators vary — some expose a dedicated field, some use a keyword or flag, and a few don't support negatives at all, in which case you describe what you want more precisely instead.

What should you put in one?

Negative prompts do two main jobs: cleaning up quality problems and refining style. Common entries include:

• Quality issues — blurry, low quality, deformed, extra limbs, mutated hands, bad anatomy.
• Unwanted extras — watermark, signature, text, logo.
• Style you don't want — if you want a flat 2D illustration, you might exclude photorealistic, 3d, shadow, glossy.
• Scene cleanup — excluding people, crowd, or clutter from an image that should be empty.

How much should you rely on it?

Start small. A short, general negative prompt handles most quality gremlins, and you only add specific terms when a particular problem keeps showing up. Piling in dozens of negatives can quietly push the image somewhere you didn't intend, so treat it as a scalpel, not a wall.

And remember it only steers — it nudges the model away from concepts, it does not guarantee they never appear.