Text & data tools
Format and convert JSON, CSV, YAML, TOML and XML, compare texts, change case, draw diagrams and count tokens. Nothing leaves your browser.
No uploads · no accounts · no tracking
Data formats
JSON Formatter
Beautify, validate & minify JSON — locally, no upload.
CSV / JSON Converter
Convert CSV to JSON and back, RFC 4180 — locally, no upload.
YAML ↔ JSON Converter
Convert YAML to JSON and back, multi-doc aware — locally, no upload.
TOML Converter
TOML ↔ JSON ↔ YAML, live, with datetime-safe round trips.
XML Formatter
Format, validate & convert XML ↔ JSON — locally, no upload.
Compare & convert text
Diff Checker
Compare two texts by line, word or character — locally, no upload.
Case Converter
camelCase, snake_case, kebab-case & more — locally, no upload.
HTML ↔ Markdown
Convert HTML to clean Markdown and back, GFM tables — locally, no upload.
Diagrams, AI & calculators
Mermaid Editor
Live Mermaid diagrams with SVG & PNG export and share links.
Token Counter
Exact GPT token counts, token view & LLM cost estimates.
Seller Fee Calculator
Net profit after eBay, Etsy, Depop & Mercari fees — runs in your browser.