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AI Data Inspector
Free tools for inspecting AI prompts, comparing models, and analyzing data. Everything runs in your browser.
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AI Tools
4 tools · free · runs in your browser
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Data Tools
4 tools · free · runs in your browser
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Inspector Tools
3 tools · free · runs in your browser
Privacy
Your data never leaves your device
Every tool runs entirely in your browser. No uploads, no servers, no tracking.
FAQ
Frequently Asked Questions
Is AI Data Inspector really free?
Yes. All tools are 100% free with no sign-up required. No credit card, no email, no limits. Just open the tool and start using it immediately.
Is my data private?
Absolutely. Every tool runs entirely in your browser. Your data never leaves your device — no uploads, no servers, no tracking. We cannot see what you type or paste.
What tools are available?
AI Token Counter, Prompt Playground, Prompt Optimizer, Model Comparator, JSON Formatter, Schema Validator, CSV Analyzer, Base64 Inspector, Text Similarity, Word Counter, and Regex Debugger — with more coming soon.
How does the AI Token Counter work?
It estimates token count and API costs locally in your browser using industry-standard estimation algorithms. Supports GPT-4o, Claude, Gemini, DeepSeek, and Llama models. No data is sent to any server.
Can I use these tools on mobile?
Yes. All tools are fully responsive and work on phones, tablets, and desktops. The interface adapts to your screen size for the best experience.
How accurate is the token counter?
Our token counter uses multi-factor estimation (character-based + word-based) achieving ~95% accuracy for English text. For exact counts, use the official tiktoken library, but our estimates are excellent for cost planning.
What is prompt engineering?
Prompt engineering is the practice of crafting inputs to AI models (like ChatGPT, Claude, or Gemini) to get better, more accurate outputs. Our Prompt Optimizer analyzes your prompts and suggests improvements.
How do I compare AI models?
Use our Model Comparator tool to see side-by-side comparisons of GPT-4o, Claude 3.5, Gemini 1.5, DeepSeek, and Llama. Compare pricing, context windows, and capabilities to find the best model for your use case.
How many tokens is 1,000 words?
About 1,333 tokens for English text, since one word averages roughly 1.3 tokens. Code, URLs, and other languages tokenize differently — the Token Counter shows the real number for your model in real time.
What is the difference between tokens and words?
A word is what you type; a token is how the model reads it. One token is about 3/4 of an English word or ~4 characters, and AI APIs bill by tokens, not words. Our counter converts both instantly.
Which AI model should I choose?
Pick by task: GPT for the broadest ecosystem, Claude for long documents and writing, Gemini for very long contexts, and budget tiers like GPT-4o-mini or Gemini Flash for high-volume work. Test them side-by-side in Model Comparator.
Guide
How AI Token Counting Works
When you send a prompt to an AI model like GPT-4o or Claude, the text is broken into tokens — small pieces of words or characters. Understanding token count is crucial because AI APIs charge based on tokens processed.
So "Hello, world!" is roughly 4 tokens. Code and non-English text often use more tokens per character.
AI Model Pricing Comparison (2026)
Different AI models have vastly different pricing. Here's what you pay per million tokens:
| Model | Input / 1M tokens | Output / 1M tokens |
|---|---|---|
| GPT-4o | $2.50 | $10.00 |
| Claude 3.5 Sonnet | $3.00 | $15.00 |
| Gemini 1.5 Pro | $1.25 | $5.00 |
| DeepSeek V3 | $0.27 | $1.10 |
| Llama 3.1 405B | $0.80 | $0.80 |
Prices refresh live in your browser from OpenRouter's public model index — new models and price changes appear automatically (static estimates shown if you're offline). Compare any of them in theModel Comparator.
Why Prompt Optimization Matters
A well-crafted prompt can reduce token count by 10-30% while producing better results. Our Prompt Optimizer analyzes your prompts for clarity, specificity, role definition, format specification, and other best practices — then suggests improvements.
Example: Instead of "Write me something about dogs," try "You are a veterinarian. Write a 200-word guide about caring for senior dogs, covering diet, exercise, and common health issues." The second prompt is more specific, defines a role, and sets clear expectations — resulting in better output with fewer tokens.
Choosing the Right AI Model
The "best" AI model depends on your use case:
- Budget-friendly: Gemini 1.5 Flash ($0.075/M) or GPT-4o Mini ($0.15/M)
- Long documents: Claude 3.5 Sonnet (200K context) or Gemini 1.5 Pro (2M context)
- Code generation: GPT-4o or Claude 3.5 Sonnet
- Privacy-sensitive: Llama 3.1 405B (self-hosted)
Use our Model Comparator to see side-by-side comparisons of pricing, context windows, and capabilities.
Blog
Latest Guides
All posts →OpenAI API Pricing Explained: What GPT-5 Actually Costs
Per-token rates for the GPT-5 family, real cost examples, and the discounts that cut your bill.
GPT-5 Token Limit & Context Window Explained
Context windows and output limits for GPT-5.5, GPT-5.4, and Nano — and what hitting them looks like.
What Is an AI Token? Simple Guide
What tokens are, how many equal a word, and why they drive every AI bill and limit.
Support
Found these tools useful?
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