Free online JSON tools — private by design

Nine developer tools that run entirely in your browser. Your JSON never leaves your machine — no uploads, no accounts, no limits. Convert, inspect, validate.

JSON to SQL

Convert JSON arrays into INSERT statements and CREATE TABLE DDL

JSON to Java

Generate Java POJOs or records from JSON, with Jackson or Gson annotations

JSON to C#

Generate C# classes or records from JSON for System.Text.Json or Newtonsoft

JSON to TypeScript

Generate TypeScript interfaces or types from JSON, with optional/nullable accuracy

JSON to JSONL

Convert between JSON arrays and newline-delimited JSON (JSON Lines / NDJSON)

JSONL Viewer

Inspect JSONL/NDJSON files with per-line validation — nothing is uploaded

JSON Schema Generator

Infer a JSON Schema (draft 2020-12 or draft-07) from sample JSON

JSON Schema Validator

Validate JSON data against a JSON Schema and see precise error paths

JSON Escape / Unescape

Escape text for embedding in JSON strings, and unescape back