AI Utility Tools
Enhance AI prompts, convert Markdown to HTML, and extract text summaries 100% privately in your browser.
Prompt Optimizer & Enhancer
Transform simple draft ideas into structured, high-performing prompts for ChatGPT, Gemini, and Claude.
Open Prompt OptimizerMarkdown to HTML Converter
Convert Markdown syntax to clean HTML markup or parse HTML back to Markdown in real time.
Open Markdown ConverterText Summarizer & Key Extractor
Extract key takeaways, core sentences, and bullet-point summaries from long articles locally.
Open Text SummarizerTiktoken & LLM Token Counter
Count tokens for GPT-4o, GPT-4, Claude, and Gemini with visual token boundaries and cost estimates.
Open Tiktoken CounterAI Utilities, Prompt Engineering & Token Calculators
Working with Large Language Models (LLMs) like OpenAI GPT-4o, Claude 3.5, and Gemini 2.0 requires structured prompt construction, token limit auditing, and Markdown rendering. DIY Toolkit provides powerful local AI helper utilities for prompt optimization, Tiktoken counting, and Markdown processing.
Real-Time Tiktoken & LLM Token Counter
Count exact sub-word tokens using o200k_base and cl100k_base encodings with visual color-coded token boundaries and API cost estimation.
Structured Prompt Optimizer
Turn basic ideas into expert system prompts with configurable personas (Software Engineer, Copywriter, Analyst) and custom output formats.
Markdown & Text Summarization
Convert LLM Markdown responses into clean HTML markup and extract core key takeaway bullet points locally.
Frequently Asked Questions
What is Tiktoken and why count tokens?
Tiktoken is OpenAI's byte-pair encoding (BPE) tokenizer. LLMs process text in chunks called tokens rather than whole words. Counting tokens helps you stay within model context windows and calculate API costs.
Are my AI prompts or tokens sent to any external API?
No. All tokenization, prompt formatting, and Markdown parsing happen 100% locally in your browser JavaScript environment.