Free developer tools, practical calculators and interview preparation resources to help you code faster, learn smarter and prepare for your next opportunity.
Fast, browser-based developer utilities.
Practical tools and resources for everyday development.
JSON, JWT, Base64, UUID, Regex, SQL and API utilities.
Programming, finance, productivity and utility calculators.
Angular, React, JavaScript, TypeScript and System Design.
DevStacker provides free online developer tools, calculators and interview preparation resources. Every tool runs directly in your browser without installation, sign-up or subscriptions.
Whether you're formatting JSON, decoding JWT tokens, preparing for technical interviews or solving everyday development problems, DevStacker helps you work faster and more efficiently.