JSON Tools Guide: Read, Repair, Convert Data

Start with the failure, not the file extension

Most JSON work begins with one of four problems. The payload is unreadable, invalid, shaped wrong, or headed somewhere else. Picking by symptom avoids a chain of conversions which changes data before anyone has checked the source.

“Unreadable at a glance.”

Open the viewer for folding or the beautifier for indentation.

“The parser rejects this.”

Use the parser for escaped strings. Pick the fixer for malformed source.

“One field changed.”

Compare responses in JSON Diff, then prove selectors in the path tester.

“Another system needs this.”

Read the loss table first. CSV, SQL, XML, YAML, and code models preserve different parts of the source.

Valid JSON has a narrow border

Browsers accept JavaScript object syntax in code. JSON parsers accept less. A pasted object with single quotes, comments, or a trailing comma is still invalid JSON.

{"service": "api.toolexe.com","retries": 3,"enabled": true}

A fixer is a diagnostic bridge, not a production parser. Repair the producer after you recover the draft. Silent repair at an API boundary turns bad input into uncertain data.

Keys and strings use double quotes. Single quotes belong to JavaScript, not JSON.
The final member has no trailing comma.
Comments are outside the JSON grammar. Keep notes in documentation or a named field.
Numbers exclude NaN and Infinity. Store an agreed string or null when no finite value exists.
Object key order carries no contract meaning. Array order often does.

Three field workflows, with a stop point

A good workflow ends before the browser starts making business decisions. Use these sequences to inspect or reshape data, then put contract checks back in the application which owns the payload.

API RELEASE

Compare staging with production

Format both responses in JSON Beautifier.
Place them in JSON Diff.
Generate a draft in JSON to JSON Schema.
Stop. Review required fields against the written API contract.

SHEET IMPORT

Turn a workbook into records

Pick the header row in Excel to JSON.
Remove blank fields in JSON Cleaner.
Test a nested selector in JSON Path Tester.
Stop. Check dates, leading zeroes, and large identifiers against the sheet.

EMBEDDED CONFIG

Place JSON inside another value

Check the source in JSON Viewer.
Use JSON Stringify for source code.
Use URL Encode for a query value.
Stop. Base64 adds transport safety, not secrecy.

The destination decides what gets lost

JSON stores trees, lists, strings, numbers, booleans, and null. Flat tables or typed classes need extra rules. No converter knows your business meaning, so review the first difficult row rather than the easiest one.

Destination	Good fit	Review before use	Page
CSV or TSV	Arrays of similar records	Nested objects, arrays inside cells, nulls, leading zeroes	JSON to CSV
Excel	Review, filtering, handoff	Large integers, date coercion, formula-like text	JSON to Excel
YAML or TOML	Readable configuration	Implicit YAML types, table structure, comments absent from JSON	JSON to YAML
SQL	Starter inserts from object arrays	Column types, keys, constraints, transactions, nested values	JSON to SQL
Typed code	Model scaffolds from representative records	Optional fields, unions, decimal ranges, dates, naming rules	JSON to TypeScript
Base64	Text-only transport	No secrecy, larger output, UTF-8 assumptions	JSON to Base64

Every JSON tool, grouped by the job

Each live tool route in the JSON category appears once below. The short note states the best fit or the boundary worth checking.

46 linked pages

Read, compare, and repair

Start here when the payload is hard to scan, fails to parse, or hides a changed field.

JSON ViewerFold nested objects, copy paths, and inspect long values without rewriting the source.JSON BeautifierIndent valid JSON, with line and column details when parsing fails.JSON DiffCompare two documents and isolate added, removed, or changed values.JSON EditorEdit a larger document with code-editor controls and syntax feedback.JSON ParserTurn an escaped JSON string back into a readable object.JSON FixerRepair common syntax faults, then review every change before reuse.JSON CleanerRemove nulls, blank strings, or empty containers while protecting chosen keys.JSON SorterOrder keys for stable review before a fixture or config reaches source control.JSON Syntax HighlightingColor tokens for a quicker scan. Highlighting does not prove validity.JSON NavigatorMove through deep objects by path without scanning the full document.JSON Path TesterRun JSONPath expressions and copy matched values or normalized paths.TOML ValidatorCheck TOML syntax before converting a configuration file into JSON.

Compact, escape, and transport

These pages change how JSON travels through source code, URLs, logs, or text-only channels.

JSON MinifierRemove ignored whitespace and report the byte change while preserving values.JSON to One LineCollapse a multi-line document into one line for logs or compact fields.JSON StringifyCreate an escaped JSON, JavaScript, or template-literal string.JSON EncodeEscape quotes, backslashes, and newlines for a JSON string value.JSON DecodeReverse an escaped string and check the decoded JSON.JSON Multiline StringPrepare multi-line text for a JSON field without broken line endings.JSON to Base64Encode UTF-8 JSON for a text-only transport. Base64 is not encryption.Base64 to JSONDecode Base64 text, then read and validate the recovered JSON.JSON URL EncodePercent-encode a payload for a query value or form field.JSON URL DecodeReverse percent encoding before parsing the recovered document.

Move data into another format

Conversion always makes a choice about nesting, types, or repeated rows. Read the destination limit first.

JSON to CSVFlatten object arrays into columns for spreadsheets or data imports.JSON to TSVWrite tab-separated rows while handling tabs, arrays, nested values, and nulls.JSON to ExcelPlace records into a workbook for sorting, review, or handoff.Excel to JSONChoose the real header row, trim stray totals, and turn a sheet into records.JSON to HTMLRender data as a table, nested list, or definition list.JSON to TextExtract keys, values, pairs, or a readable text tree.JSON to XMLSet the root and array strategy before objects become XML elements.JSON to YAMLWrite YAML with chosen indentation while checking values YAML 1.1 might retype.JSON to SQLBuild INSERT statements or a starter table from an object array.JSON to JSON LinesPut one record on each line for streaming or batch jobs.JSON to ProtoDraft Protocol Buffers fields from a sample JSON shape.TOML to JSONTurn a TOML configuration into a JSON document for another system.JSON to TOMLMap objects into TOML tables for configuration files.

Generate types, models, and contracts

A sample payload gives these generators evidence, not certainty. Optional fields need more than one representative record.

JSON to JavaDraft Java classes from nested objects and arrays.JSON to PHP ArrayConvert JSON objects and lists into PHP array syntax.JSON to PythonCreate dataclasses, Pydantic models, TypedDicts, or plain classes.JSON to TypeScriptCreate interfaces, aliases, classes, or Zod schemas from sample records.JSON to C#Draft classes or records with nullable and serializer options.JSON to JavaScriptWrite an object literal, module export, class, or JSDoc typedef.JSON to GoBuild structs with JSON tags, pointer choices, and date detection.JSON to DartCreate model classes with fromJson, toJson, and copyWith methods.JSON to Objective-CDraft Objective-C model declarations from a payload shape.JSON to JSON SchemaInfer a schema draft, set required rules, then test a second payload.

Create test records

Use repeatable mock data when an endpoint or fixture is missing.

Random JSON GeneratorDefine fields, set a seed, and produce repeatable JSON or NDJSON records.

Questions worth asking before the output ships

Syntax is only the first check. Privacy, type inference, flattened data, and silent repair carry bigger risks once a payload reaches another system.

Should broken JSON go through the fixer before production?

Use the fixer to learn what broke and to recover a draft. Do not turn repair rules into a silent production parser. Fix the producer, add validation at the boundary, then reject malformed input with a useful error.

Why do CSV and Excel lose parts of a nested object?

Rows and columns have no native object tree. A converter must flatten nested keys, stringify nested values, or split data across sheets. Check the preview before a spreadsheet becomes the only copy.

Does Base64 protect private JSON?

No. Base64 changes bytes into printable text. Anyone with a decoder gets the original payload. Use encryption or a protected transport when secrecy matters.

Which page fits an API response I need to inspect?

Open JSON Viewer for folding and paths. Pick Beautifier for readable indentation plus syntax errors. Use JSON Diff when two environments return different data, or JSON Path Tester when one selector needs proof.

Does pasted JSON leave the browser?

The pages in this guide process input in page scripts. File converters read the selected file inside the tab. A browser page is still the wrong place for secrets on a shared machine or a profile loaded with untrusted extensions.

Why does generated code mark the wrong field as required?

One sample proves only what appeared once. Feed several representative records where the generator accepts arrays, then review nullability, integer ranges, dates, and names against the real API contract.

{ }

One rule worth keeping

Validate before conversion. Inspect after conversion. When the destination introduces types or constraints, test the result there too.