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Tool Animated Word Cloud — View animated word cloud visualizations that use an Archimedean spiral placement algorithm to position words on a canvas. Each word spirals outward from the center until it finds an unoccupied space, with grid-based spatial indexing accelerating collision detection to handle large datasets efficiently. Control the animation playback speed, step through frames manually, download the final result as a PNG, or paste your own text to generate a custom word cloud.
Tool Unicode Explorer — Binary Search Over HTTP — View Unicode characters and their properties through an interactive binary search algorithm that makes real HTTP Range requests to fetch individual records from a binary database. Enter a character or Unicode codepoint to see each step of the search visualized in a network log, including fetch times and comparisons.
Tool Mobile Data Tables: Responsive Patterns Demo — # Mobile Data Tables: Responsive Patterns Demo
Tool Contact form — Submit contact information through this responsive form that provides real-time validation using native HTML5 attributes and CSS-only feedback. The form validates required fields including name, email, and message content, displaying checkmarks for valid inputs and error messages for invalid entries without requiring any JavaScript.
Tool Gemini Prompt — Generate responses from Google's Gemini API with support for system prompts, model selection, and streaming output. The interface stores your API key securely in local storage and maintains a history of system prompts for quick reuse. Markdown formatting is automatically rendered in the output area, and you can copy responses to your clipboard with a single click.
Tool Gradient image generator — Generate customizable gradient images with multiple pattern overlays and effects. This tool provides controls for linear, radial, and conic gradients with adjustable colors, along with options for layering various patterns including noise, geometric shapes, and textures. Additional features include film grain, vignetting, and blend mode controls to fine-tune the visual appearance, with the ability to export the final result as a PNG image or save and restore settings as JSON.
Tool Python Comment Stripper — Remove all comments from Python source code while preserving strings, docstrings, and code structure using the `tokenize` module running on Pyodide. Paste your Python code into the input panel, and the tool automatically strips comments in real-time, with the ability to copy the cleaned output to your clipboard. The application runs entirely in the browser without requiring a local Python installation.
Tool Pyodide REPL — Execute Python code directly in your web browser using Pyodide, a port of CPython to WebAssembly. This REPL provides an interactive Python environment with support for multiple Pyodide versions, single-line and multi-line input modes, and command history navigation. The interface is optimized for both desktop and mobile devices, with a dark theme and responsive layout that prevents content from being hidden behind on-screen keyboards.
Tool GIF Dissector — Parse and visualize animated GIF files by extracting individual frames, timing data, color palettes, and detailed metadata. Upload a GIF file to instantly decompose it into its constituent frames with precise delay measurements, disposal methods, transparency information, and global color table analysis. The tool renders composited frames to show exactly how the animation appears, while providing comprehensive technical details about the image structure and properties.
Tool SQLite AST — Parse SQLite SELECT queries into abstract syntax trees and view the results in JSON and Python representations. This tool uses the sqlite-ast library running in your browser via Pyodide to analyze SQL syntax and display both the dictionary-based parse tree and a rich pretty-printed representation. It supports complex queries including compound selects, common table expressions, and window functions, and can display partial parse results when encountering syntax errors.
Tool Minesweeper — Play a classic Minesweeper game directly in your browser with support for three difficulty levels: Easy, Medium, and Hard. Use left-click to reveal cells and right-click to place flags, or toggle between reveal and flag modes on mobile with long-press support. The game features a timer to track your speed, mine counter to monitor remaining flags, and immediate visual feedback when you win or hit a mine.
Tool Bookmarklets Collection — Access a collection of practical bookmarklets for web development and general browsing tasks. Each bookmarklet can be installed by dragging it to your bookmarks bar on desktop browsers or by copying the code for mobile Safari. The collection includes tools for revealing page anchor points and viewing page source code with formatting options, all presented with detailed documentation and source code inspection capabilities.
Tool Seamless Sandboxed Iframe Prototype — Embed untrusted content safely within a webpage using a sandboxed iframe that automatically adjusts its height without allowing cross-origin access. The prototype uses `postMessage` to communicate height changes between the sandboxed iframe and parent page, enabling seamless content display while maintaining security restrictions. Various content examples demonstrate how the sandbox handles dynamic content, images, and attempts at malicious behavior.
Tool Lobsters Latest Comments Bookmarklet — Browse Lobste.rs comment threads with an enhanced "Latest" tab that displays all comments in chronological order with newest first, making it easier to catch up on recent discussion activity. The bookmarklet adds reply-to links showing parent comment relationships and includes a "Copy Thread" feature to export the entire discussion as numbered plain text.
Tool v86 Linux Emulator — Run Linux commands in your browser using x86 emulation powered by v86, a JavaScript/WebAssembly-based x86 emulator. This tool executes a minimal Buildroot Linux distribution directly in your browser, with typical boot times between 10-30 seconds depending on your device and connection speed. Enter commands in the input field to interact with the Linux shell and view output in the terminal window.
Tool Red Annotation Extractor — # Red Annotation Extractor Documentation
Tool Hyperviz — Create real-time audio-reactive visualizations with eight distinct modes including plasma, particles, tunnel effects, kaleidoscope patterns, Matrix rain, terrain, fire, and starfield animations. The visualizer captures frequency data from your microphone and responds dynamically to bass, mid, and high frequencies, with beat detection triggering visual flashes and intensity changes.
Tool Software Heritage Repository Retriever — Download archived Git repositories from Software Heritage, the universal archive of software source code. This tool queries the Software Heritage GraphQL API to locate repositories and creates downloadable bare Git archives through the vault service. Enter a repository URL to retrieve the latest snapshot and access detailed archive information including the Software Heritage identifier (SWHID) for future reference.
Tool Cooking Timer — # Cooking Timer Documentation
Tool PG&E Outage Map - Half Moon Bay Area — Track power outages affecting the Half Moon Bay area with this interactive map displaying real-time PG&E outage data within a 15-mile radius. The application visualizes outage locations as point markers and affected areas as polygons, while displaying key statistics including the number of outages, impacted customers, and affected regions. Custom markers can be added by providing a URL parameter, and the map automatically refreshes every five minutes to ensure current outage information.
Tool MicroQuickJS Code Executor — Execute JavaScript code in a lightweight MicroQuickJS sandbox environment running via WebAssembly, with results displayed directly on the page. The sandbox supports ES5-like JavaScript features and automatically saves your code in the URL for easy sharing and recovery. Choose between optimized and original WebAssembly versions, try built-in examples, and use Ctrl+Enter to quickly run your code.
Tool llm-lib demo — This is an interactive demonstration of a unified JavaScript library that provides a consistent interface for working with multiple large language model providers. The tool allows users to seamlessly switch between OpenAI, Anthropic Claude, and Google Gemini while managing API keys and configuring system prompts. Both streaming and non-streaming response modes are supported, with real-time status updates and syntax-highlighted code examples showing how to integrate the library into projects.
Tool Photo print layout — Create custom photo print layouts for A4 pages with adjustable grid configurations, image fitting options, and portrait or landscape orientations. Users can add photos by uploading files or dragging and dropping them directly onto the page, then remove individual photos or clear the entire layout before printing. The preview displays actual print dimensions, allowing precise control over how photos will appear on the final printed output.
Tool CSS Grid Lanes Polyfill Demo — # CSS Grid Lanes Polyfill Demo
Tool JSON Diff Tool — Compare JSON documents side-by-side to identify additions, removals, and modifications between two versions. The tool displays differences with color-coded highlighting and provides character-level detail for string changes, making it easy to spot exactly what has changed. Preloaded examples are available to explore common use cases like configuration updates, user profile changes, and API response comparisons.
Tool Claude Code Timeline Viewer — View Claude Code session `.jsonl` files as an interactive timeline with customizable filtering and search capabilities. This tool displays events chronologically, extracting conversation messages, tool calls, and file snapshots with formatted previews of text content, code blocks, and embedded images. Use the file picker, drag-and-drop, paste input, or URL fetch to load your session data and explore it with timezone switching, content-type filters, and easy JSON export.
Tool Codex Timeline Viewer — View Mozilla Codex rollout timeline events from `.jsonl` files with an interactive interface that supports filtering, searching, and detailed event inspection. Load files via drag-and-drop, paste, or URL fetch, then explore events organized chronologically with customizable timezone display and comprehensive event details including formatted content, tool calls, and reasoning blocks.
Tool QuickJS Code Executor — Execute JavaScript code in a sandboxed QuickJS WebAssembly environment with a built-in synchronous `fetch()` function for retrieving remote content. Code is automatically encoded in the URL hash, allowing you to easily share executable snippets with others. The interface provides a collection of ready-to-run examples covering common programming tasks and JavaScript features, making it useful for learning, testing, and demonstrating code behavior.