Make an unreadable response inspectable
Use JSON formatting for indentation and syntax errors. If the response is one JSON object per line, choose the JSONL viewer instead of treating the whole log as a single document.
JSON Formatter →
Choose by task
JSON, YAML, CSV & SQL Tools
Choose a tool to format structured data, validate an API contract, compare JSON, convert CSV, or prepare schemas, types and SQL fixtures.
Browse these tools ↓Which tool should you start with?
Start with the question your data needs to answer. A formatter makes syntax readable; a schema validator checks a contract; a structural comparison finds changes in values and types. Keeping those steps separate makes a failed API response or configuration file easier to diagnose.
Explain what changed between two payloads
Compare JSON by field path when key order and whitespace would overwhelm a text diff. Check the reported old value, new value and type before accepting a change.
JSON Diff →Check whether an object satisfies a contract
Paste the expected schema with the data to inspect required fields and types. Generate a draft schema only when you still need to write the contract; a sample alone cannot prove all valid shapes.
JSON Schema →Check the result before the next step
Keep an original sample, validate its syntax, then inspect the fields you actually need. Before exporting a conversion, check large numbers, nulls, dates and nested arrays. Inferred schemas and generated types describe the samples you supplied; review optional fields and missing cases against the real contract.
Data
JSON Formatter, Minifier & Validator
Format, minify, and validate JSON with useful line and column errors. Your data stays entirely in this browser.
Runs locally DataJSON Schema Validator
Validate JSON against common Draft 2020-12 schema keywords and see every issue by data path. Runs locally in your browser.
Runs locally DataJSON Diff & Semantic Compare
Compare two JSON documents by path and find added, removed, changed, and type-mismatched values without uploading data.
Runs locally DataJSONPath Tester & Query Evaluator
Evaluate practical JSONPath expressions, inspect matched paths and values, and copy results without sending JSON to a server.
Runs locally DataJSON to Go, TypeScript, Java & Python Types
Generate Go structs, TypeScript interfaces, Java records, or Python dataclasses from sample JSON entirely in your browser.
Runs locally DataCSV to JSON & JSON to CSV Converter
Convert CSV, TSV, or semicolon-delimited tables to JSON and JSON arrays back to CSV with delimiter, header, and pretty-print controls.
Runs locally DataJSONL / NDJSON Viewer & Filter
Inspect newline-delimited JSON logs, filter records by text or field, find malformed lines, and export valid records without losing numeric precision.
Runs locally DataYAML Formatter & Validator
Catch common YAML indentation and structure errors, then normalize readable configuration locally in your browser.
Runs locally DataYAML to JSON Converter
Convert common YAML documents to JSON and JSON back to readable YAML without uploading configuration data.
Runs locally DataSQL Formatter, Minifier & Beautifier
Format or minify SQL for MySQL, PostgreSQL, SQLite, and SQL Server with configurable keyword case. Runs locally.
Runs locally DeveloperDeveloper Data Pipeline
Build a reusable browser-local workflow such as Base64 decode → JSON format → JSONPath extract, then run it in one click.
Runs locally DataJSON Test Data Generator
Generate repeatable JSON or CSV fixtures from a sample, with field rules, sequences, date ranges, enums and null rates.
Runs locally DataJSON to Schema & Field Documentation
Infer JSON Schema from one or several samples, review required-field assumptions, and export a Markdown field reference.
Runs locally DataJSON / CSV to SQL INSERT Generator
Generate PostgreSQL or MySQL INSERT scripts locally, with explicit table names, column mapping and exact numeric values.
Runs locally DataJSON Field Mapper & Structure Builder
Move or copy JSON fields to new nested paths, preview the result and reuse the mapping in a local pipeline.
Runs locally