GraphQL Playground - Online Query & Schema Explorer
Execute GraphQL queries against any endpoint with variables and headers. Explore schema via introspection. All requests made directly from your browser.
UD5 Toolkit
Test your GraphQL endpoints instantly. Enter the URL, query, optional variables & headers, and get the response in a clean, formatted view.
Key: Value format.Send a request to see the response here.
Access-Control-Allow-Origin header, requests will be blocked. You can use a browser extension, a CORS proxy, or configure your server to allow your origin.Authorization: Bearer eyJhbGciOiJIUzI1NiIs...mutation { createUser(name: "Jane") { id } }. The tool sends a POST request with your exact payload, so both queries and mutations are supported.$variableName syntax and that the variables object includes a matching key.Execute GraphQL queries against any endpoint with variables and headers. Explore schema via introspection. All requests made directly from your browser.
Build a GraphQL query by selecting fields and nesting visually. Copy the built query string. For learning and fast prototyping.
Open many parallel WebSocket connections and send messages. Test your server's concurrency. All from your browser.
Paste a JSON object and see a dynamic, draggable tree graph representation. Excellent for debugging nested data.
Paste a JSON array and filter/transform it using a simple path expression. Extract nested values without code. Local.
Set a cron expression and see a calendar of the next 1,000 execution times. Never miss a schedule again.
Fill in a form to generate a valid package.json for your Node.js project. Includes popular scripts and fields. Local only.
Test prompt formatting without calling an LLM. See how your prompt would look with different templates. Dev tool.
Plot one or more mathematical functions f(x) on a 2D canvas. Zoom, pan, and see intersections. Great for calculus and algebra. Purely client‑side.
Search and extract values from a large JSON object using dot/bracket notation. Quickly locate deeply nested fields. Data stays local in your browser.
Paste a sample JSON object and generate a basic JSON Schema describing its types and required fields. Local inference.
Generate random icebreaker questions for meetings, parties, or classrooms. Categories for work, fun, and deep talks.
Fill in plaintiff, defendant, claim details and organize supporting documents. Print a summary for court. Local only.
Run the classic FizzBuzz with custom rules. See the output for any range. A beginner programmer's playground.
Paste a JSON array and view it as a formatted console.table() style output. Copy for terminal apps. Local.
Enter processes and see how different scheduling algorithms handle them. Gantt chart generation. OS course helper.
Paste a JSON Schema and automatically render a complete, styled HTML form with validation. Perfect for prototyping APIs. Works entirely in the browser.
Generate a LocalBusiness structured data snippet with name, address, phone, and opening hours. Boost local SEO.
Generate pure audio tones of specific frequencies (Hz). Adjust waveform type (sine, square, sawtooth). Ideal for audio testing and science experiments.
Input any JavaScript object and see if structuredClone can deep‑copy it. Compare with JSON.parse/stringify. Learn transferables.
Log your coin collection with country, year, grade, and images. Filter and export as spreadsheet. All data local.
Create a Review or aggregateRating structured data. Perfect for star ratings in search results. Copy the code.
Play low-frequency tones to check subwoofer phase alignment with main speakers. Simple tool.
Build cron expressions using a visual editor with dropdowns. See human-readable description and next run times. Easier than raw cron.
Convert a flat JSON object into a Java .properties file format. Handle nested values by dot notation. Local only.
Experience the four stages of rock tumbling virtually. Start with rough stones and watch them polish over 'days'. Satisfying.
Watch a simulation of how the JavaScript event loop handles synchronous code, microtasks, and macrotasks. Learn async.
Paste a JSON object and generate PlantUML code for a class or object diagram. Preview rendered image.
Perform simple or regex-based find and replace operations on text. Batch replace words, phrases, or patterns instantly. Processed locally in your browser.
Online JSON formatting and validation tool, supporting JSON minify/beautify, syntax highlighting, and error locating. Data processed locally in browser for security.