27.07.2025

Free Web Tools that I find useful

These tools are free, mostly open source, and mostly process data locally in your browser without hitting the server.

Dev

CyberChef: The Swiss army knife for encoding/decoding strings and data analysis
npmgraph: Visualize npm dependencies as a graph
Better Mobile Inputs: Tester for for various input types and how they trigger your smartphone's virtual keyboard

Flems.io: Small playground for web stuff, stores data in the URL. Useful for sharing bugs etc. on GitHub without creating a repo or gist
Favicon.io: Favicon generator
RealFaviconGenerator: Generates a lot of different formats, maybe too many
ColorHexa: Create and convert colors
Color Hunt: Color palettes
CSS Gradient: Create CSS gradients
CSS Shadows: Create CSS box shadows
Shapefactory Gradients: Another CSS gradient generator

QR Code Generator: No BS! Support for logos, different shapes etc.
EPC-QR Code Generator (girocode): Lets you generate an EPC QR Code for your bank account so that friends can scan this and wire you money without typing an IBAN (Fotoüberweisung)

Understanding SVG Paths: An interactive tutorial for learning how to write SVG paths from scratch
SVG Path Visualizer: Explains SVG Paths
SVGO(ptimizer): Take SVG files, simplify paths, compress
SVG Path Editor: Raw editing of SVG paths
SVGRepo: Tons of open-licensed SVG vectors and icons

excalidraw: Cool little tool to create all sorts of schematic drawings, a nice hand-drawn effect optional
tldraw: Useful little drawing program, similar to excalidraw
perfect freehand: Same author as tldraw, the freehand-tool basically extracted as a standalone app
Icon Maker: Create simple app icons

asciiflow: Draw ASCII diagrams for your documentation
flowchart.js: Create flowchart diagrams with JS or text directly in your browser
Mermaid: Create Mermaid diagrams in your browser with text

DonkeyCase Generator: fOr WHen yoU NeEd THat donkEycasE to MaKE yoUr poiNt
Related subreddits: Graph of related subreddits for a given sub
Map of Reddit: Map of Reddit
Youglish: Don't know how to pronounce an English word? This tool searches YouTube videos for your word and plays the exact moment the word is spoken
paste: Simple text editor that lets you share text stored in the URL
Fantasy City Map Generator: City generator (links to HN, first comment has many more fantasy generators)
TipToiTool: Tool to mess with your kid's TipToi
Settlers Setup: Generate a more fair Catan playing board
Dashboard Deutschland: Visualization of many things regarding Germany