Skip to content
JSON Toolkit
Deploy
Features

Everything JSON Toolkit can do

39 sharp, focused tools — all running privately in your browser with no account and no data uploads.

39

Tools

8+

Input formats

6

View modes

7

Themes

What's new

Fresh off the workbench

The latest improvements, shipped in the last few releases.

JSON ↔ TOON

New

Convert JSON to TOON for LLM prompts and back again, with real token counts for TOON, minified JSON, and formatted JSON side by side.

Try now

JSON mapper

New

Convert JSON from one schema to another: fields auto-match by name, arrays map item by item, and the mapping exports as JavaScript.

Try now

JSON Blob share links

New

Share JSON with a single link. The document is compressed into the link itself, so nothing is uploaded or stored anywhere.

Try now

Markdown viewer

New

Open a .md file or paste a GitHub repo link to read its README rendered like GitHub — tables, task lists, alerts, highlighted code — with a live side-by-side editor and HTML or PDF export.

Try now
idnametags
1Alice[json, dev]
2Bob[api]
3Carol[infra, sre]

Nested grid view

New

The grid viewer now renders nested objects and arrays as inline sub-tables — see your whole structure in one screen, no clicking required.

Try now

JSON file viewer

New

A file-first page with a big drag-and-drop zone — open a .json, CSV, Excel, or ZIP file and read it instantly as a collapsible tree, all in your browser.

Try now

Save & reuse datasets

New

Save any input under a name to a private, on-device library — stored compressed — then load or copy it back into any tool, on any visit.

Try now

Seven professional themes

New

A redesigned theme set — One Dark, Nord, Solarized, and more — with your pick remembered across visits.

Try now

39 tools across four categories

Format & Validate · View & Explore · Compare & Search · Convert

Browse all tools
Input

Get your data in — any way you want

Upload files

Drag-and-drop or click to upload

  • JSON (.json)
  • CSV & TSV (.csv, .tsv)
  • Excel (.xlsx, .xlsm) — converted to a JSON array instantly
  • YAML (.yaml, .yml)
  • XML (.xml)
  • Plain text (.txt)

Load from URL

Fetched directly in your browser — no server proxy

  • Any public JSON, CSV, or Excel URL
  • Raw GitHub file links
  • API endpoint responses
  • CDN-hosted data files
  • ZIP archive URL — pick which file inside to view

Paste anything

Tolerant parser auto-normalises it

  • Valid JSON
  • Stringified / double-encoded JSON
  • Python dicts (True, False, None, tuples)
  • JS object literals with unquoted keys
  • Single quotes, trailing commas, comments (// # /* */)
  • Markdown code-fenced blocks
Views

6 ways to see your data

Switch views without leaving the page. Every mode is optimised for a different task.

{
"name": "Alice",
"age": 30,
"active": true
}

Formatted

Syntax-highlighted with 2/4/tab indent or single-line minify. Recursively sort keys.

▾ root{3}
├─ name: "Alice"
├─ age: 30
└─ ▾ tags[2]
└─ "json"

Tree

Collapsible hierarchy with search, type badges, and one-click copy of any path.

idnameage
1Alice30
2Bob25
3Carol28

Table

Arrays of objects as sortable, filterable rows — nested fields flattened to dot-notation columns.

idnametags
1Alice[json, dev]
2Bob[api]

Grid (Nested)

New

Renders nested objects and arrays inline as sub-tables within each cell — see the full structure at a glance.

▸ root / users / [0]
name
Alice
age
30
active
true
role
admin

Grid (Drill-down)

Spreadsheet one level at a time — click any cell to step into nested objects or arrays, navigate back with breadcrumbs.

  "id": 1,
- "name": "Alice",
+ "name": "Bob",
  "age": 30,
~ "role": "admin"

Diff

Git-style side-by-side comparison with added/removed/changed markers, plus order-independent structural diff.

Themes

7 themes, one click

Pick your palette from the theme selector in the top bar. Your choice persists automatically.

Dark
One Dark
Nord
Solarized Dark
Light
Solarized Light
System
The details

Everything in the box

Missing a feature?

Need a different format, a new view, or a conversion that isn't here yet? Send a request — every suggestion is read and most end up shipping.

Contact us