Fast, free tools for working with JSON — format, validate, convert, and query, all running locally in your browser. No data ever leaves your machine.
Convert JSON data into a formatted, printable PDF document.
Tokenize JSON for LLMs — count tokens, inspect token boundaries, and estimate API cost.
Convert JSON configuration files to the TOML format used by Rust and others.
Generate and validate JSON Schema from sample data or validate documents against a schema.
Query JSON documents using JSONPath expressions and inspect the results live.
Decode and inspect JWT tokens — header, payload, and signature — without any server.