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JSON Inspector

Paste JSON to explore it as a collapsible, searchable tree, hide the fields you don't need, and see the structure it implies as a badge-annotated schema and a copyable TypeScript interface.

Everything runs locally in your browser. Your data never leaves your device.

Input

Model

The structure inferred from your JSON.

Data

FieldsUntick to hide

Next steps

Keep going. These tools open with your result loaded in.

Config Converter

Convert config and data between JSON, YAML, TOML, JSON5, INI, XML, CSV and .env. Type or paste on the left, pick the output format on the right, and copy the result. Includes a format button and a minify toggle.

devconverterconfigjsonyaml

JSON Diff

Compare two JSON documents by structure and see every added, removed and changed key and value with its exact path. Browse the result as a tree, a filterable change list or a line diff, ignore array order, catch type changes and export the changes as a JSON report.

devjson

JSON Inspector

Paste JSON to explore it as a collapsible, searchable tree, hide the fields you don't need, and see the structure it implies as a badge-annotated schema and a copyable TypeScript interface.

devjson

Text Case Converter

Convert text into every case at once: title case in the APA, AP, Chicago, MLA, Bluebook, AMA and NYT styles, sentence case, upper, lower, camelCase, snake_case, kebab-case and more.

textconverter

Word & Character Counter

Count words, characters, sentences, paragraphs, lines and more as you type, with estimated reading and speaking time.

text

Dedupe Lines

Remove duplicate lines from a list or text, keeping the first occurrence. Optionally ignore case and whitespace, or drop blank lines too.

textdev

Find and Replace

Replace text in two modes: plain find and replace all, or regular expressions with flag controls and capture group references like $1.

textdev

Text Diff

Compare two texts and see every added, removed and changed line highlighted, side by side or inline, with the changed words marked within each line. Ignore case, whitespace or blank lines, read a summary of how much changed, and export the result as a unified diff.

textdev

UUID Decoder

Paste a UUID to see what it carries: version, variant, and for time-based versions the exact timestamp, clock sequence and node. Also shows the raw bytes, the 128-bit integer and the URN form.

devuuid

About the JSON Inspector Tool

This tool helps you read and understand a block of JSON. Paste it in and it shows the data as a tree you can expand, collapse and search, then works out the shape as a schema and a TypeScript interface you can copy.

It is aimed at API responses and config you need to make sense of quickly, without hunting through a wall of text.

What you can do

  • View and format JSON as a collapsible tree.
  • Generate a TypeScript interface from JSON.
  • See the inferred schema, with optional and nullable fields and detected formats.
  • Search keys and values, and copy any value or its JSONPath.
  • Hide fields you do not need before copying or downloading.

How to use the JSON Inspector

  1. 1Paste or type your JSON into the input editor.
  2. 2Click Format to tidy it, or read the error if the JSON is invalid.
  3. 3Read the schema and the TypeScript interface in the Model section, and copy the interface if you need it.
  4. 4Switch between the tree and formatted views, and search to jump to a field.
  5. 5Hide any fields you do not need, then copy or download the result.

From JSON to a TypeScript type

The inspector reads your JSON and works out a type for it, then writes that out as a TypeScript interface. Fields missing from some records become optional, mixed types become unions, and common string shapes like emails, URLs and dates are labelled. Copy the interface straight into your code.

Standard JSON only

It reads standard JSON, the same as your code would. Comments, trailing commas, single quotes and JSON5 are not accepted, and an invalid document shows an error with the line and column so you can find the problem.

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devtextjsonyaml

Config Converter

Convert config and data between JSON, YAML, TOML, JSON5, INI, XML, CSV and .env. Type or paste on the left, pick the output format on the right, and copy the result. Includes a format button and a minify toggle.

devconverterconfigjsonyaml

Fake Data Generator

Generate realistic fake data for testing: names, emails, addresses, phone numbers, companies, internet data, dates and more. Tick the fields you need, set how many rows you want and a locale, then copy or download the result as JSON, CSV or plain text.

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HAR Viewer

Drop a HAR export from your browser's network tab and see every request on a waterfall timeline. Inspect status codes, timings, sizes, headers and payloads, filter by type or URL, and spot the slow requests at a glance.

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jq Playground

Run real jq filters against JSON in your browser. Write a filter, pass options like slurp or raw output, browse a built-in cheat sheet of common filters, and copy the result or send it to another tool.

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JSON Diff

Compare two JSON documents by structure and see every added, removed and changed key and value with its exact path. Browse the result as a tree, a filterable change list or a line diff, ignore array order, catch type changes and export the changes as a JSON report.

devjson