ToolStack

ToolStack is 38 free online tools built for developers, marketers, writers, and creators. No signup, no paywalls, instant results. Tools include: JSON Formatter, JWT Decoder, SQL Formatter, Grammar Checker, Paraphrasing Tool, Hashtag Generator, QR Code Generator, Invoice Generator, UTM Builder, Regex Tester, CSS Gradient Generator, and 27 more. Every AI tool runs on GPT-4o. Everything works in your browser — zero data stored, zero accounts required.