8 Working Tools · 100% Local

Engineer prompts like a power user

A premium single-page toolkit for AI prompt engineers. Build structured prompts, browse 30+ curated templates, test prompt quality, estimate tokens & cost, compare LLMs, and assemble few-shot prompts — all running entirely in your browser.

8
Tools
30+
Templates
9
LLMs Compared
0
Server Calls

Prompt Builder

Build a structured, best-practice prompt in seconds. Pick a task, role, tone, length, and format — the builder assembles a clean, copy-ready prompt using proven prompt engineering patterns.

1 · Task 2 · Role 3 · Topic 4 · Tone 5 · Length 6 · Format
Writing Image Generation Code Analysis Brainstorming
Professional Friendly Persuasive Authoritative Playful Empathetic Technical
Generated Prompt
A structured prompt ready to paste into ChatGPT, Claude, Gemini, or any LLM.
Click "Generate Prompt" to build your structured prompt.

Prompt Library

Browse 30+ curated prompt templates across 7 categories. Click any card to expand the full prompt, then click "Use" to fill in the variables and generate a final, ready-to-run prompt.

Use Template
Fill in the variables above and click Generate.

Temperature & Token Guide

Drag the sliders to explore how temperature and max tokens shape model output. See live examples, word/token estimates, and projected API cost across GPT-4, GPT-3.5, and Claude.

0.70
0.0 – 0.3
Deterministic
Factual, repeatable. Best for code, math, data extraction.
0.3 – 0.7
Focused
Coherent with slight variety. Good for analysis, summaries.
0.7 – 1.0
Balanced
Default for most chat. Creative yet on-topic.
1.0 – 1.4
Creative
More variance, ideation, brainstorming, fiction.
1.4 – 2.0
Chaotic
Wild, often incoherent. Rarely useful in production.
Max Tokens
Maximum number of tokens the model can generate in its response.
1000
~750
Approx Words
~50
Approx Sentences
~1.5
Approx Pages
Rule of thumb: 1 token ≈ 4 characters ≈ 0.75 words in English. 1 page (single-spaced, 12pt) ≈ 500 words ≈ 670 tokens.
Estimated API Cost (output only)
At current published rates. For reference only — verify with the provider before billing decisions.
Costs above assume you generate the full max-tokens budget on every call. Real usage is usually lower. Input tokens are billed separately and not included here.

Model Comparison

Side-by-side comparison of 9 major LLMs. Filter by use case to find the right model for your task. Pricing reflects published per-1M-token rates at the time of writing.

Filter by use case
Model Context Knowledge Cutoff Input / 1M Output / 1M Strengths Best For
Context window is the maximum combined input+output tokens. "Knowledge cutoff" is the latest training data date. Prices are per 1,000,000 tokens in USD.

Prompt Tester

Paste a prompt and get an instant heuristic analysis: clarity, specificity, and structure scores (0–100), estimated token count, and a list of potential issues with concrete suggestions.

Variable Injector

Paste a prompt template containing {{variables}}. The tool auto-detects every variable, builds a form, and replaces them with your values. Save templates to localStorage for reuse.

Variables detected: 0
Detected variables will appear above. Fill them in and click Generate.
Saved Templates
Stored in your browser's localStorage. Persist across reloads on this device.
No saved templates yet.

Few-Shot Builder

Assemble a few-shot prompt: a system message, one or more input→output examples, and a final query. Few-shot prompting teaches the model the desired pattern by demonstration. Save templates to localStorage.

Generated Few-Shot Prompt
Add at least one example and a final query, then click Generate.
Saved Few-Shot Templates
No saved templates yet.

Token Counter

Paste text to get an instant token estimate, word & character counts, projected API cost across major models, and a per-sentence token distribution chart. Uses the heuristic: 4 chars ≈ 1 token with word-boundary adjustment.

0
Est. Tokens
0
Words
0
Characters
0
Sentences
Estimated Cost (input tokens)
Token Distribution by Sentence

Frequently Asked Questions

Everything you need to know about the Premium AI Toolkit.