About Cathode Labs
We build free, privacy-first developer tools that run entirely in your browser. No accounts, no tracking, no data leaves your machine.
Categories
Developer
JSON, Base64, JWT, Regex — the essentials
4 tools
Text
Transform, diff, and analyze text
4 tools
Security
Hash, encrypt, and inspect security primitives
4 tools
Math
Calculate, convert, and visualize numbers
4 tools
Design
Color, typography, and layout tools
4 tools
Network
DNS, IPs, headers, and connectivity
4 tools
Business
Invoice, estimate, and manage — freelancer essentials
2 tools
Finance
Quick money math, tax, and compound calculations
3 tools
Philosophy
Great tools should be free and private. Every tool on Cathode Labs processes data entirely in your browser using client-side JavaScript. Nothing you input is ever sent to a server.
No accounts to create. No cookies tracking you. No premium tiers gating basic functionality. Just open a tool and use it.
We believe developer tools shouldn't require you to trust us with your data. By keeping everything client-side, we don't have to ask for your trust — the code running in your browser speaks for itself.