Free AI Tools That Run Offline

Helpers for working with large language models and machine learning that run entirely in your browser: plan prompts, prepare datasets, protect private data and learn how models work, with no API key and no data sent anywhere.

Token CounterExact GPT token counts, plus Claude and Gemini estimates LLM Cost CalculatorCompare API costs across GPT, Claude, Gemini and more Context Window PlannerBudget system prompt, docs, history and reply RAG Text ChunkerSplit documents into chunks for embeddings Prompt Template BuilderReusable prompts with {{variables}} and CSV batches Prompt LibraryCopy-ready prompts for writing, code and study JSONL ValidatorCheck fine-tuning and batch JSONL files line by line Function Calling Schema BuilderBuild tool definitions for OpenAI, Claude and Gemini PII RedactorRemove personal data before pasting into AI Text Similarity CheckerCompare two texts: cosine, Jaccard and edit similarity Chat to MarkdownSave ChatGPT and Claude conversations as Markdown AI Image Size GuideBest sizes for DALL·E, Midjourney, SDXL and Flux Temperature & Top-p VisualiserSee how temperature, top-k and top-p change outputs Markov Chain Text GeneratorGenerate text from your own sample, word or letter level Neural Network PlaygroundTrain a small neural network in your browser K-Means Clustering VisualiserWatch k-means cluster points step by step Embedding VisualiserPlot embeddings in 2D with PCA and find neighbours Prompt CompressorShorten prompts and save tokens AI Text CleanerRemove Markdown, em dashes and chatbot filler