Prompt quality, measured

Know your prompt's quality before you send it.

Caliber lives inside Claude, ChatGPT, Gemini and Perplexity. It scores your draft 0 to 100 as you type, tells you what's holding it back, and rewrites it in one click, your way. And it's the one that measures whether that rewrite actually helps, then publishes the number.

Get early access See the benchmark
Free during the beta · runs in your browser
Caliber · Live scorer0 words
/ 100
weak
Works on Claude/ChatGPT/ Gemini/Perplexity
How it works

In the box you already use.

01

Draft as usual

A gauge scores your prompt 0–100 as you type and flags what's missing, right beside the composer.

02

Know what's weak

The score breaks into what changes an answer: specificity, context, constraints, output format.

03

Rewrite your way

Pick a mode — add a role, go detailed, or keep it tight. Accept drops the rewrite into the box.

The honest part

Everyone claims better prompts. We publish the number.

A blind benchmark: the same tasks, original prompt versus optimized, judged by a stronger model in both orders to cancel position bias. This is the real pilot result — including that most comparisons were inconclusive. No other prompt tool shows you this.

Benchmark · pilotn = 15
0%
optimized win-rate
95% confidence interval23–88%
Decisive comparisons5 / 15
VerdictUnproven
The interval includes a coin flip and most comparisons were inconclusive, so we don't claim it works yet. A bigger corpus tightens it — and the method is public.
Privacy

Your prompts stay yours.

Scoring runs in your browser. Your conversation memory lives in the page and is erased when the tab reloads.

You control your data. Usage stats are anonymous and off-switchable; sharing prompt text is opt-in only.

Never sold, never used to train other models. No exceptions.

ClaudeChatGPTGeminiPerplexity
Early access

Running in two minutes.

It's a Chrome extension. During the beta:

  1. Download the extension folder.
  2. Open chrome://extensions and turn on Developer mode.
  3. Click Load unpacked and select the folder.
  4. Open a supported AI site, sign in, and start typing.