21 free tools for developers. JSON, Base64, Regex, JWT, UUID, SQL formatting, diff checker, hash generator, QR code and more. All processing happens in your browser — no data ever uploaded.
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ToolsStack is a free collection of 21 online developer tools that run entirely in your browser. All processing happens client-side — no data is ever uploaded to any server, ensuring your data stays private and secure. Tools include JSON formatter, Base64 encoder/decoder, JWT decoder, hash generator, diff checker, regex tester, QR code generator, and more.
Yes, all tools are completely free. There are no paid tiers, no sign-up requirements, and no usage limits. Because every tool runs client-side in your browser, we have no server processing costs to offset — which means we can keep everything free, permanently.
Yes. All tools process data entirely in your browser using JavaScript. No data is ever uploaded, stored, or transmitted to any external server. You can verify this by opening your browser's Network tab while using any tool — you will see zero outbound data requests. This is a core design principle of ToolsStack.
ToolsStack offers 21 tools across four categories. Developer: JSON Formatter, JSON to CSV, Base64 Encode/Decode, URL Encoder/Decoder, HTML Entity Converter, JWT Decoder, SQL Formatter, Regex Tester, Hash Generator (MD5/SHA-1/SHA-256/SHA-512), PDF Compressor, PDF to JPG. Generators: UUID Generator, Password Generator, Lorem Ipsum Generator. Text Tools: Word Counter, Case Converter, Diff Checker, Markdown Preview. Image & Color: Color Picker, QR Code Generator, GIF Maker.
No. All tools work directly in your web browser with no installation, no sign-up, and no browser extensions required. Just visit toolsstack.org, pick a tool, and start using it immediately.