Prompts loaded. Click Compare Prompts to see which is stronger.

Prompt Builders

Prompt Comparator

Paste two prompt alternatives and find out which one is better — and why. Scores for clarity, specificity, structure, output control, risk, and efficiency, with strengths, gaps, and improvement suggestions for each. Runs entirely in your browser.

Paste the first prompt you want to evaluate.

Paste the second prompt to compare against Prompt A.

Comparison Focus

Weights the overall score toward what matters for your decision.

Use Case (optional)

Adds use-case-specific checks to the report.

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Playbooks that use this tool

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Prompt Builder Workflows · 4 steps

AI Prompt Engineering Workflow

Fix an unreliable prompt the methodical way instead of poking at it — find what's actually unclear, rewrite for specificity, cut the noise, then prove the new version beats the old one.

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How it works

Paste two prompt alternatives into Prompt A and Prompt B, pick an optional comparison focus (overall quality, clarity, structure, output control, risk, token efficiency, or model readiness), and click Compare Prompts. The comparator scores each prompt on eight dimensions using deterministic heuristics — no AI call, nothing leaves your browser — then gives you a verdict, a category-by-category comparison, each prompt's strengths and gaps, and concrete improvement suggestions. It never rewrites your prompts; it helps you decide between them.

Use cases

  • Deciding between two prompt drafts before committing one to a workflow or template library
  • Showing a teammate why one prompt version produces better output than another
  • Checking whether a shorter prompt loses anything that the longer alternative controls
  • Evaluating a prompt you found online against the one you already use

Pro tips

  • Set the Comparison Focus to what actually matters for your decision. The same pair can score differently when you care about token efficiency versus output control.
  • A close call is a real answer. When scores are within a few points, pick using the single dimension that matters most — the category table shows exactly where they differ.
  • Longer isn't stronger. The efficiency score penalises words that don't add control — a 40-word prompt with format, audience, and length guidance routinely beats a 200-word ramble.
  • Use the improvement suggestions on the winner too. The point isn't just picking A or B — it's shipping a better prompt than either.

FAQ

How are the scores calculated?

With deterministic, rule-based heuristics that run in your browser: detected signals like audience, output format, length guidance, constraints, vague wording, contradictions, and repetition feed eight dimension scores, which are weighted by your chosen comparison focus. No AI model is called and your prompts never leave the page.

Is this a diff tool?

No. A diff tool answers "what changed between v1 and v2 of the same prompt." The comparator answers a different question: "which of these two prompts is better, and why?" It compares quality and intent coverage, not lines.

What if the two prompts are nearly identical?

The comparator detects that and says so instead of inventing a winner. Edit one of the prompts to create a real alternative, then compare again.

Does it rewrite or improve my prompts?

No. It scores, explains, and suggests — the improvement suggestions are short, actionable notes you apply yourself. If you want structural reformatting use the Prompt Formatter; for removing repetition and noise use the Prompt Cleaner.

What does the Comparison Focus change?

The weighting of the overall score. "Token Efficiency" makes brevity count more; "Output Control" rewards format, length, and constraint instructions; "Risk & Ambiguity" punishes contradictions and vague wording hardest. The eight per-dimension scores themselves don't change.

Can the winner still be a weak prompt?

Yes — winning only means better than the other one. Check the winner's own Risks / Gaps section: if both prompts are missing an audience and output format, the report will say so for both.