Free AI Prompt Checker
Paste a prompt to get a score out of 100, a letter grade, and three clear ways it could be stronger. The checker diagnoses your prompt; it never rewrites it.
Free checks: 10 per IP address for visitors, or 30 per account for signed-in users, with a shared 100 per IP address signed-in ceiling, each per 24-hour window. A check counts once it reaches the AI provider, including if it fails or you close the page.
How the score works
Every prompt starts at 10 points. The checker looks for a clear task and role, useful context, a requested output format, constraints, tone, examples, ordered steps, and an intended audience. Those pieces add up to 100 points. It scores structure, not whether the AI's answer will be accurate.
Example: give the AI a job it can actually follow
Weak prompt
Write about exercise.
More specific version
Act as a beginner fitness coach. Write a friendly 300-word guide for office workers starting a walking routine. Include a three-day starter plan and two safety tips. Avoid medical claims.
The example shows how task, role, audience, format, and limits make a request easier to follow. The checker only diagnoses your own prompt.
Frequently asked questions
Is the prompt checker free?
Yes. Visitors can run 10 checks per 24-hour window per IP address. Signed-in users can run 30 per account per 24-hour window, subject to a shared ceiling of 100 signed-in checks per IP address. A check counts once it reaches the AI provider, even if it fails or you close the page.
Does the checker rewrite my prompt?
No. It gives a score, grade, one strength, and three weaknesses with short hints. The optimizer is a separate tool for rewriting.
How is the score calculated?
The score starts at 10 points. Clear tasks, roles, context, output format, constraints, tone, examples, steps, and audience awareness can raise it to 100.
What does a high score mean?
A high score means the prompt includes many useful structural details. It does not guarantee that any AI response will be correct.
Which AI tools can I check prompts for?
Choose ChatGPT, Claude, Gemini, Midjourney, DALL-E, or Other before checking.
Can I improve the prompt after checking it?
Yes. Use “Fix it with the optimizer” to carry your prompt into the full PromptWizz optimizer.