JSON tools
Debugging an API response, cleaning up a config file, or turning a messy export into something usable — JSON is the format you run into every day. These tools cover the everyday JSON tasks: formatting minified payloads, validating syntax before you commit, repairing broken JSON from logs or hand-edited files, and browsing large JSON or JSONL files without your editor freezing or a slow paste crashing the tab.
Pick JSONPath tester for quick path lookups, JMESPath tester when you need slicing and functions, or the jq playground when you already think in jq filters and want to copy a working command. JSON formatter keeps large IDs and decimals exact instead of rounding them, and JSON repair highlights each proposed fix so you can accept or reject changes one at a time. Everything runs in your browser; nothing is uploaded anywhere.
23 tools
Format and validate JSON
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JSON formatter
Format JSON with exact numbers while keeping large IDs and decimals intact
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JSON validator
Validate JSON syntax and find duplicate-key warnings with error positions
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JSON repair
Propose JSON fixes with highlighted changes and individual acceptance
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Large JSON viewer
Browse large JSON files in chunks without uploading or freezing
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JSONL viewer
Find line errors in JSONL files and inspect records without parsing failures
Convert JSON to other formats
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CSV to JSON Converter
Convert CSV and TSV to JSON with header and type handling
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JSON to CSV
Convert JSON arrays to CSV with explicit column selection and header control
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JSON to YAML
Transform JSON to YAML preserving exact number types and indentation style
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YAML to JSON
Convert YAML to JSON preserving root type and controlling anchor expansion
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JSON to TOML
Transform JSON objects to TOML sections with table and array-of-tables syntax
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TOML to JSON
Parse TOML to JSON preserving dates as strings and handling unsafe integers
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JSON to XML
Map JSON to XML with custom roots, attributes and array element naming
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XML to JSON
Map XML to JSON with configurable attribute handling and array detection
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JSON to Markdown table
Generate Markdown tables from JSON with custom columns and field reordering
Compare, merge and extract data
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JSON diff
Compare API responses and configs to find actual data changes
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JSON merge
Combine JSON with explicit precedence rules and inspect conflicts before exporting
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JSON flatten
Turn nested JSON into typed paths or restore it from flat keys
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JSON key extractor
List keys, select fields and convert JSON entries with deduplication
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String escape
Escape or unescape strings for JSON, JavaScript and Unicode contexts
Query JSON with JSONPath and jq
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JSONPath tester
Find values and their paths in nested JSON using JSONPath query syntax
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JMESPath tester
Filter and reshape JSON using JMESPath expressions with live results
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jq playground
Run real jq 1.8.2 on JSON or text, inspect stdout and exit codes, then copy the command
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JSON Pointer
Locate exact values using RFC addresses and parse the paths they contain
JSON tools FAQ
JSONPath is a small query language built into many libraries and the JSONPath tester here, good for quick "find this path" lookups. jq is a full filter language with its own syntax for transforming, reshaping and piping data through multiple steps — try the jq playground when a single path expression isn't enough.
Most JSON parsers convert numbers to JavaScript's double-precision float, which loses precision above 2^53 — common with 64-bit database IDs. The JSON formatter here parses numbers as text instead, so large IDs and long decimals print back exactly as you pasted them, with no silent rounding.
Often, yes. JSON repair looks for common problems — trailing commas, missing quotes, single quotes instead of double — and proposes fixes with the change highlighted, so you accept or reject each one instead of trusting a blind auto-fix. Run JSON validator first to see the exact error position.