AI & LLM
Understand tokens, estimate model costs, and build better prompts.
Tokenizer Playground
See exactly how text becomes tokens, then compare the cost across popular LLMs.
Token Counter
Count characters and LLM tokens with a lightweight, private text workspace.
Token Cost Calculator
Estimate input and output spend with transparent per-million-token pricing.
RAG Chunking Playground
Preview RAG chunks with six strategies, real token counts, source offsets, and exportable results.
AI JSON Repair + Schema Validator
Repair malformed model JSON, inspect every change, and validate detailed JSON Schema constraints locally.
Prompt Diff & Version Compare
Compare prompt revisions by line, word, or grapheme with real token deltas and optional local versions.
Structured Prompt Builder
Build deterministic prompts from typed fields, CO-STAR or RTF structures, ordered examples, and explicit local templates.
Prompt Batch Variable Expander
Expand {{variable}} prompts from JSON or CSV records with warnings, paginated previews, and lossless exports.
Prompt Template Formatter
Fill {{variable}} placeholders from JSON and identify any values your prompt still needs.
Context Window Budget
Measure prompt tokens and calculate the context left after reserving space for model output.
LLM API Request Builder
Build native OpenAI, Anthropic, and Gemini request JSON, cURL, JavaScript, and Python examples without API keys or model calls.
AI Text Cleaner + Invisible Character Inspector
Inspect invisible Unicode at original UTF-16 offsets, selectively clean copied text, and audit every local change.