Free tool · runs in your browser
AI Prompt Optimizer
Paste a rough prompt. See what it is missing, get a clearer version side by side with your original, and read what changed and why. Free, no sign-up, and it runs in your browser.
Paste your rough prompt
What we found in your prompt
Open in ChatGPT
Open in Claude
Copy and open GeminiWhat changed and why
Fill in any [BRACKETS] with your own facts before you send it. The score uses the same 5 checks as the Prompt Analyzer: it shows what a prompt is missing, not how good the AI's answer will be. To write it right the first time, keep the free prompt-writing checklist (PDF) next to your screen.
What the optimizer adds, and why
Most weak AI answers come from a prompt that leaves out what the AI needs to know, not from the AI itself. The optimizer checks your prompt for five things and adds only the parts that are missing, using the same approach as our guide to writing AI prompts. Anything you already wrote stays in.
| Part | What it does | Example it might add |
|---|---|---|
| 1. Role | Tells the AI which expert to think like, so it uses the right words and standards. | Act as a career coach who has hired people for this kind of role. |
| 2. Task | One direct line that starts with the action, so the job is clear in the first few words. | Task: Write an email to my manager asking for a salary review. |
| 3. Your facts | Blanks in [BRACKETS] for things only you know, like who it is for and your results. |
2-3 results I can point to: [RESULT WITH A NUMBER] |
| 4. Format | The layout and length you want back, so you do not get a wall of text. | A short opening, 2-3 points backed by results, then one clear ask |
| 5. Rules | Tone, a length limit and what to avoid, including a rule against made-up facts. | Under 220 words. Do not invent facts, numbers or quotes. |
It does not use AI to rewrite your words. It works with fixed rules in your browser, so the result is predictable and private. For image and video prompts with camera, lighting and style words, try the Prompt Doctor.
Explore all free prompt tools
Prompt Doctor
See what your prompt is missing and get a fixed version that keeps your own words. Works for image and video prompts too.
Open Prompt Doctor →Prompt Analyzer
Score any prompt out of 100 across 5 checks of 20 points: task, context, format, limits and details, with a reason for each.
Open Analyzer →Prompt Converter
Translate prompts between ChatGPT, Claude, Midjourney parameter tags, and video tools like Veo and Kling.
Open Converter →Questions, answered
How does the Prompt Optimizer work?
It checks your prompt for five things: a clear task, context, an output format, limits and concrete details. It keeps everything you wrote and adds only the parts that are missing, such as a role, blanks for your facts, a format and a few rules. Then it lists each change and why it helps.
Does the optimizer send my text to an external AI server?
No. The optimizer runs in your browser with fixed rules. Your prompt is not sent to PromptUp or to any AI company.
What are the [BRACKETS] in the improved prompt?
They are blanks for facts only you know, like [YOUR RESULTS] or [WHO IT IS FOR]. Replace them with your own details before you send the prompt to ChatGPT, Gemini or Claude.
Does a better score mean a better answer?
Not always. The score counts signals such as a format or a rule, so it is a guide to what is missing, not a promise. A short prompt can still work well for a simple question. See how the score works.
Can I change the improved prompt?
Yes. The After box is editable, and the copy and open buttons use your edited text. You can also build a prompt from scratch with the Prompt Builder.