language/json
A JSON Editor that Formats and Validates as You Type
Paste JSON and the editor formats it, folds it and flags a misplaced comma on the line it happens, so a broken document is fixed where you can see it, with nothing to install.
{
"name": "xcodx",
"version": "7.6.0",
"tags": ["ide", "browser", "json"],
"private": true
}01 platform
What a code editor gives JSON that a text box can't
Most JSON problems are small and structural — a trailing comma, a wrong bracket, a value that should have been a string. A real editor catches those where they happen instead of failing later when something tries to parse the file.
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Format on command
Turn a minified blob into indented, readable JSON in one keystroke, or collapse it back. Prettier-style formatting is built in, so a pasted response becomes something you can actually read.
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Validation as you type
The editor checks the JSON continuously and underlines a syntax error the moment you make it — a duplicate key, an unquoted name, a stray comma — so it never reaches whatever was going to consume the file.
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Fold any node
Collapse objects and arrays to see the shape of a large document, then expand only the branch you care about. Monaco's folding turns a 2,000-line config into something navigable.
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Private by construction
The JSON is parsed and formatted in your browser and never uploaded, which matters when the file is a config, a token dump or an API response you would rather not paste into a random website.
02 deep dive
Format, fold and validate as you type
The three things you actually do to a JSON file — make it readable, navigate it, and confirm it is valid — are the three the editor is built around.
Beautify or minify in one step. A command reformats the whole document with consistent indentation, or strips it back to a single line. Pasting a compressed API response and reading it is a two-key operation.
Folding shows the structure. Every object and array gets a fold control, so you collapse the noise and keep the branch you are editing open — the fastest way to understand a deeply nested config.
Validation is continuous. There is no separate validate button to press; the editor marks a problem as you type and clears it as you fix it, so the document is either valid or visibly not.
- beautify
- one command
- minify
- one command
- fold
- per object/array
- validate
- continuous
{
"server": { … },
"features": [ … ],
"limits": { "max": 100, "burst": 20 }
}03 features
What the JSON editor handles
Everything below is on the moment you open the JSON editor, which starts with a small, valid document you can reshape.
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Beautify & minify
Reformat to readable, indented JSON or compress to one line, on command — a formatter and beautifier in one, both a keystroke away.
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Live error checking
A misplaced comma, an unclosed bracket or a duplicate key is underlined as you type — a live validator with a message and a line, so an invalid file is obvious before anything parses it.
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Import .json files
Drop a .json file into the project and edit it directly — the starter template imports one as a parsed object, so real data is one drag away.
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Big files stay navigable
Folding, the minimap and fast find make a large config or a bulky API response something you can move around in rather than scroll endlessly.
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Sits beside your code
A JSON file lives in the project tree next to the code that reads it, so a config and its consumer are edited together, not in two different tabs of two different tools.
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Private and offline
Everything happens in the browser with nothing uploaded, and it keeps working offline as a PWA — safe for the config and credential files people paste into JSON tools every day.
04 deep dive
Where a JSON error actually is
The whole value of validating JSON is being told exactly where it broke, because the failure is almost always one character.
The error points at the line. A trailing comma after the last element, a single quote where JSON needs a double, a value with no key — each is underlined at the spot it occurs, with a message that names the problem.
Duplicate keys are flagged. JSON allows them and most parsers silently keep the last, which is a bug waiting to happen; the editor warns you so a config does not quietly ignore half of what you wrote.
Strict JSON, on purpose. Comments and trailing commas are not valid JSON, and the editor holds that line, so what passes here is what a strict parser elsewhere will accept — no surprises when the file is actually loaded.
- syntax
- line + message
- duplicates
- flagged
- strict
- no comments/commas
- fix
- where it happens
{
"a": 1,
"b": 2,
}
// ^ trailing comma — not valid JSON05 workflow
From pasted JSON to a clean, valid file
No upload, no install, no round trip to a server — the whole loop from a minified blob to a formatted, validated document.
- paste minified JSON (1 line, 4KB)
- parsed · 1 syntax error highlighted
- fix trailing comma on line 1
- valid · no errors
- format document
- beautified · 142 lines, 2-space indent
- fold to top level
- 3 keys · structure at a glance
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Nothing leaves the browser
The JSON is never uploaded, so formatting a config or an API response with secrets in it is safe in a way a random online formatter is not.
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The same loop on a phone
Parsing and formatting run client-side, so a phone cleans up a JSON file the same way a laptop does, offline if need be.
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It is just a file
The result is a plain .json file in your project, ready to commit, export or hand to the code that reads it.
06 ecosystem
JSON beside the rest of the toolkit
JSON is one of many things the editor handles — the same tab edits a config, compiles the code that reads it and previews the result, per file.
07 languages
What the editor edits alongside JSON
A JSON file sits beside everything else the editor compiles in the browser, renders natively, or runs on demand.
Compiled in your browser11
Zero build step. Transform runs on a Web Worker, so typing never blocks.
- JSX
- TSX
- TypeScript
- Vue SFC
- Svelte
- Angular (JIT)
- SolidJS
- SCSS
- Sass
- Less
- Pug
Rendered natively8
Straight to the live preview, no transform in the way.
- HTML
- CSS
- JavaScript
- JSON
- Markdown
- Jupyter (.ipynb)
- SVG
- YAML
Executed on demand22
70+ languages run through a self-hosted Piston engine. stdout, stderr, images and tracebacks land in the console.
- Python
- Java
- C
- C++
- C#
- Go
- Rust
- Ruby
- PHP
- Kotlin
- Swift
- Lua
- Scala
- Perl
- Haskell
- Elixir
- Dart
- R
- Julia
- SQLite
- Bash
- PowerShell
08 questions
JSON in the browser — common questions
Can I format and beautify JSON here?
Yes. One command reformats the whole document with consistent indentation, and another minifies it back to a single line. Pasting a compressed API response and making it readable is a two-key operation, with nothing to install.
Does it validate JSON as I type?
Yes. The editor checks the document continuously and underlines a syntax error — a trailing comma, an unclosed bracket, an unquoted key — the moment you make it, with a message and a line number, so an invalid file never slips through.
Is my JSON uploaded anywhere?
No. Parsing, formatting and validation all happen in your browser and nothing is sent to a server, which is what makes it safe to clean up a config, a token dump or an API response you would not paste into an unknown website.
Does it show a tree or graph view of the JSON?
Not a node-graph like some dedicated viewers. This is a code editor: you get formatting, code folding to collapse and expand any object or array, a minimap and fast search — the structure through the text rather than a separate diagram.
Does it warn about duplicate keys?
Yes. Duplicate keys are technically allowed by JSON and most parsers silently keep the last one, which hides bugs; the editor flags them so a config does not quietly drop half of what you wrote.
Can I edit JSON beside the code that uses it?
Yes. Projects are multi-file, so a config sits in the tree next to the code that reads it, and you edit both in one place instead of switching between a formatter tab and your editor.
Does it allow comments or trailing commas?
No, because strict JSON does not, and the editor holds that line on purpose. What validates here is what a strict parser elsewhere will accept, so there are no surprises when the file is actually loaded.
Do I need to install anything to use XCODX Studio?
No. XCODX Studio is a browser-based IDE — the editor, the compilers and the preview all run client-side. There is no download, no package manager to set up and no configuration file to write. Opening the editor is the whole setup step.
Where is my code stored?
In your own browser. Projects, file history and Git objects live in local storage on your device and are never uploaded to a server. That also means XCODX works offline: it is a Progressive Web App, so you can install it and keep coding with no connection.
Is XCODX Studio free?
Yes. The editor, the live preview, the 70+ language runtimes, npm installs, Git and the integrated terminal are all free to use.
Can I use XCODX on a tablet or Chromebook?
Yes. The editor is a responsive web app, so a Chromebook, an iPad or an Android tablet gets the same compilers and the same preview a laptop does — there is no desktop-only build, because there is no build to install at all. The layout adapts to the screen rather than shrinking a desktop UI into it.
Can I export a project or move it to my own machine?
Yes. Export the whole project as a zip with its folder structure intact and open it locally, or commit it and push. It is ordinary source on disk from that point on — no proprietary format and no lock-in, which is also why importing an existing repository from GitHub works the same way in reverse.
Nothing to install
Open the JSON editor now
A formatted, validated document on screen in under a minute — private, in the browser, with no account wall and nothing to install.