Devsly
Developer tools that just work. Zero config. Zero BS.
Devsly is a free collection of developer tools that run in the browser. Format JSON, encode Base64, generate hashes, decode a JWT, test a regex, convert a cURL command. No signup, no ads.
In its first year it reached 100K+ developers in 10 countries, with 1,039,271 interactions and 850,355 API requests across 78 free tools.
It is MCP-ready too: all 78 tools run straight from an AI assistant, and the architecture is published. A Security Hall of Fame thanks the researchers who keep it safe.
What it does
- 78 free tools, from JSON and Base64 to WHOIS and DNS lookup
- No signup, no ads, nothing to configure
- MCP-ready: every tool one command away inside your AI assistant
- Public API with published docs
- Free Chrome extensions: Devsly Network Tools, HookFlow Webhook Tester, Proxy Pilot
- Security Hall of Fame and a 2026 bug-bounty program
Stack
- Browser tools
- MCP
- REST API
- Chrome extensions
- English / Turkish
Gallery
▶ Best Developer Tools: 73 Free Tools and MCP
▶ Best AI Agent Skills on GitHub: DevSly's Best Skills Page in 3 MinutesLinks
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