109+ Free
Developer Tools
Free Developer Tools & System Design Resources
Browser-based tools that run instantly — no installs, no data sent to servers, no accounts needed.
Popular Tools
Explore our most-used categories — every tool runs entirely in your browser.
Code Formatting
JSON formatter, HTML beautifier, SQL formatter & more
Encoding & Decoding
Base64, URL encoding, hex, binary converters
Security & Crypto
Hash generators, password tools, encryption utilities
API & Network
API tester, HTTP header viewer, DNS lookup
Text Utilities
Word counter, case converter, lorem ipsum generator
Data Conversion
JSON ↔ YAML, CSV ↔ JSON, unit converters
Why SWE Helper?
Built with a simple philosophy — developer tools should be fast, free, and private.
100% Browser-Based
Every tool runs entirely in your browser. Your data never leaves your device — total privacy by design.
Lightning Fast
No server round-trips means instant results. Format, encode, decode, and convert in milliseconds.
No Signup Required
Jump straight in — no accounts, no emails, no paywalls. Every tool is free and immediately accessible.
Open Source
Built by developers, for developers. Transparent code you can inspect, contribute to, and trust.