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wtf is json-schema-dev?

relequestual/json-schema-dev — explained in plain English

Analysis updated 2026-07-20 · repo last pushed 2026-02-18

20VueAudience · developerComplexity · 2/5MaintainedSetup · easy

TL;DR

A free in-browser playground for writing and testing JSON Schema against sample data. It runs validation entirely client-side so your data never leaves your machine, and lets you share schemas via a link.

Mindmap

mindmap
  root((repo))
  What it does
    Write JSON Schema
    Test sample data
    Share via link
  How it works
    Runs in browser
    Uses AJV validator
    No server round trips
  Tech stack
    Vue.js
    Netlify
  Use cases
    Debug validation errors
    Share schemas with others
    Quick JSON testing
  Audience
    API developers
    Config file authors

Code map

Detail Auto

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filefunction / class

Why would anyone build with this?

REASON 1

Paste a schema and sample data to check if the data passes validation.

REASON 2

Share a link with a colleague to debug a confusing validation error together.

REASON 3

Experiment with JSON Schema rules to learn how different validation keywords work.

REASON 4

Test schemas intended for API request and response validation before deploying them.

What's in the stack?

Vue.jsAJVNetlify

How it stacks up

relequestual/json-schema-devjohnc628/vue-sfcsduhbbx/skylerx
Stars202021
LanguageVueVueVue
Last pushed2026-02-18
MaintenanceMaintained
Setup difficultyeasyeasyeasy
Complexity2/51/52/5
Audiencedevelopervibe coderdeveloper

Figures from each repo's GitHub metadata at analysis time.

How do you spin it up?

Difficulty · easy Time to first run · 5min

Runs entirely in the browser via Netlify with no backend or API keys required.

Wtf does this do

jsonschema.dev is a free online tool that lets you write and test JSON Schema documents directly in your browser. Think of it as a playground or scratchpad: you type out a schema on one side, some sample data on the other, and immediately see whether the data passes or fails validation. The closest analogy is something like JSFiddle, but specifically built for the JSON Schema community. JSON Schema is a way to describe what a valid JSON document should look like, which fields are required, what types they should be, what format a date or email should follow, and so on. It's widely used in the real world. VS Code uses it under the hood to provide autocomplete and validation for configuration files. OpenAPI (formerly Swagger) relies on a subset of it to define API request and response shapes. Tools like Webpack and ESLint also depend on it. The tool exists because the JSON Schema community needed an easy way to share and debug schemas collaboratively. If someone runs into a confusing validation error, they can paste their schema and data into the site and share a link rather than trying to explain the problem in text. Unlike some other online validators that send your data to a server for processing, this one runs entirely in your browser using a validation library called AJV. That means no round-trips to a server and your data never leaves your machine. The project is built with Vue.js and deployed automatically through Netlify, which also generates preview links for pull requests so contributors can review changes before they go live. Contributions are welcome but should be directed at the develop branch, not master. If you work with APIs, configuration files, or any system that involves structured JSON data, this is a handy tool to have bookmarked for quick testing and troubleshooting.

Yoink these prompts

Prompt 1
I want to build a feature like jschema.dev where a user pastes a JSON Schema and some JSON data in side-by-side panels and instantly sees validation errors. How should I structure the Vue.js components and use AJV for client-side validation?
Prompt 2
Help me create a JSON Schema that validates an object with required fields name (string), email (email format), and age (integer >= 18), and show me example JSON that would pass and fail this schema so I can test it in a playground like jschema.dev.
Prompt 3
I have a JSON Schema that gives a confusing validation error when I validate my data. Here is the schema and the data, can you help me find the mistake and explain which keyword is causing the failure?

Frequently asked questions

wtf is json-schema-dev?

A free in-browser playground for writing and testing JSON Schema against sample data. It runs validation entirely client-side so your data never leaves your machine, and lets you share schemas via a link.

What language is json-schema-dev written in?

Mainly Vue. The stack also includes Vue.js, AJV, Netlify.

Is json-schema-dev actively maintained?

Maintained — commit in last 6 months (last push 2026-02-18).

How hard is json-schema-dev to set up?

Setup difficulty is rated easy, with roughly 5min to a first successful run.

Who is json-schema-dev for?

Mainly developer.

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