Answer three questions
“Write an Instagram caption for my bakery's new sourdough.” PromptLab expands it into role, task, tone and output format automatically.
PromptLabWhere ideas become instructions.
PromptLab is the workbench for prompt craft. Simple when you need it, deeply powerful when you don't — one adaptive flow for beginners, creators, professionals and prompt engineers.
Precision PromptsCreate SmarterWhere Ideas Become InstructionsThe Science of PromptingBuild Prompts Like a ProMaster the Language of AI
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Live demoType an idea the way you'd say it out loud. Watch PromptLab turn it into a professional prompt with a role, tone, constraints and output format.
(01) Built for every skill level
Shape the voice
Pick the Content Creator persona, nudge humour up and formality down, and get a hook → body → payoff → CTA structure every time.
Engineer the spec
Editable role/task/context blocks, seven tone sliders, banned and required phrases, {variables}, versioning and refinement passes.
(02) The Battle Arena
You can't get this anywhere else
One prompt. Three AIs. One winner.
The Arena runs your prompt through three top models at the same time, grades every answer against your own rules — tone, structure, word limits, banned phrases — and patches whatever leaked through. Proof, not guesswork.
Enter the Arena94
GPT-6 Astra★ winner
Followed every rule
78
Gemini 3.8 Flash
Ignored the word limit
61
Gemini 3.1 Pro
Broke tone · used banned phrase
(03) The Reverse Prompt Decompiler
Exclusive to PromptLab
Paste writing you admire. Get the prompt behind it.
The Decompiler works backwards from finished output to the instructions that made it: role, task, audience, all seven tone dials, the constraints, and the named techniques with quoted evidence — rebuilt as a prompt with {variables} you can edit and reuse.
Decompile your first promptRole
A B2B outbound strategist writing to operations leads
Technique
Cost-of-inaction opener anchored to a concrete number
Tone
high directness · low formality · very low humor
Variables
{prospect_name} · {peer_companies} · {time_saved}
(04) Community examples
14 real, complete prompts across all seven personas — copy any of them into your own library the moment you sign in.
Browse all examples(05) Seven expert personas
Each persona rewrites tone, structure, vocabulary and reasoning depth — the same idea, told the way a specialist would tell it.