Practice AI image prompts, with a score
The fastest way to get better at prompts is feedback. Prompt Duel gives you a target image, 60 seconds, and a score for how close your prompt gets.
▶ Play freeWhat you practice
- Subject first: models weigh the start of a prompt most.
- Style words: "watercolor", "isometric 3D", "35mm photo" change the whole image.
- Specific details: colors, materials, lighting and setting.
- Brevity: 60 seconds forces you to keep only words that matter.
How the score works
A CLIP model running in your browser compares your generated image with the target. 65% of the score is how well your image shows what the secret prompt describes, and 35% is how similar it looks. Vague prompts like "a colorful picture" score low, which is the point.
How to write AI image prompts: a 4-part formula
- Subject: what is it, and what is it doing? "a fox sleeping".
- Details: material, clothing, number, size. "a fox made of origami paper".
- Setting and light: "on a snowy windowsill, soft morning light".
- Style: "watercolor illustration", "35mm photo", "low-poly 3D".
Practice the formula against a timer and a score. That is the whole idea of Prompt Duel, and it is a quicker way to get better at AI image prompts than reading another prompt guide.
Weak vs strong prompt
| Weak | Strong |
|---|---|
| a cute bird picture | an owl made of orange autumn leaves sitting on a tree branch |
| a nice city at night | neon-lit rainy Tokyo street at night, reflections on wet asphalt, cinematic photo |
| a funny cat | a grumpy orange cat wearing a tiny wizard hat, cartoon style, purple background |
Example round
“an owl made of orange autumn leaves sitting on a tree branch”
“a cute bird picture”
Questions
Is this a good way to learn prompt engineering?
For image prompts, yes: each round is a short exercise with a clear target and an instant score, so you see which words actually change the result.
Which AI model makes the images?
Images are generated with FLUX.1 schnell, a fast open image model.
Is it free?
Yes. No account, no download, no ads.