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
Add a root field to start building your query.
Execute GraphQL queries against any endpoint with variables and headers. Explore schema via introspection. All requests made directly from your browser.
Enter a GraphQL endpoint, write a query, and see the response. Add headers and variables. Simple testing client.
Paste a JSON object and see a dynamic, draggable tree graph representation. Excellent for debugging nested data.
See interactive Venn diagrams for SQL JOINs: INNER, LEFT, RIGHT, FULL, CROSS. Understand set theory visually. Local static site.
Parse a URL's query string into a key-value table, or build a query string from parameters. Perfect for API testing and web development.
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.
Paste a JSON array and filter/transform it using a simple path expression. Extract nested values without code. Local.
Format and beautify SQL queries for improved readability. Supports various SQL dialects. Quick syntax highlighting and local processing ensure a secure experience.
Simulate paint colors on a pre-loaded room photo by adjusting hue, saturation. Find your perfect shade before buying. Local canvas.
Drag an angle around the unit circle and see sin, cos, tan values change live. Degrees and radians display. Perfect for learning trig.
Watch a simulation of how the JavaScript event loop handles synchronous code, microtasks, and macrotasks. Learn async.
Build cron expressions using a visual editor with dropdowns. See human-readable description and next run times. Easier than raw cron.
Search and extract values from a large JSON object using dot/bracket notation. Quickly locate deeply nested fields. Data stays local in your browser.
Drag a battery, resistor, LED onto a grid and simulate current flow. Show Ohm's law in action.
Generate random icebreaker questions for meetings, parties, or classrooms. Categories for work, fun, and deep talks.
Fill in a table name and columns, and the tool writes the correct SQL INSERT, UPDATE, DELETE, and SELECT queries. For quick scaffolding.
Create a basic Open Graph image with a title, background color, and logo. Download as PNG. Perfect for small sites.
Enter your FAQ questions and answers, and get ready‑to‑paste JSON-LD structured data. Boost search appearance.
Fill in a form to generate a valid package.json for your Node.js project. Includes popular scripts and fields. Local only.
Open many parallel WebSocket connections and send messages. Test your server's concurrency. All from your browser.
Set a cron expression and see a calendar of the next 1,000 execution times. Never miss a schedule again.
Paste a JSON Schema and automatically render a complete, styled HTML form with validation. Perfect for prototyping APIs. Works entirely in the browser.
Run the classic FizzBuzz with custom rules. See the output for any range. A beginner programmer's playground.
Acquire and release locks across tabs. Prevent race conditions in IndexedDB or localStorage. Visual queue and lock state.
Upload an image and see its 2D FFT magnitude and phase. Learn how image filtering works. Educatinal tool. Canvas.
Generate a QR code with a custom text label below or above. Perfect for printed signs. All generated locally as a single image.
Enter a list of words and generate a custom word search puzzle in PDF/PNG format. Great for teachers and parties. Local.
Compute confidence intervals for a population mean (known/unknown sigma) and proportion. All popular Z/T values. Local.
Paste a sample JSON object and generate a basic JSON Schema describing its types and required fields. Local inference.
Create a Review or aggregateRating structured data. Perfect for star ratings in search results. Copy the code.