About DevToolStack

Why this site exists

Developers reach for small utilities dozens of times a day: format this JSON, decode that Base64 string, generate a UUID, count some characters. Most online tools that do these jobs run your input through their backend — which means the API responses, tokens, and customer data you paste can be logged, stored, and leaked. In late 2025, security researchers found that two of the most popular formatting sites had been retaining years of user submissions, including live credentials from banks and government agencies.

DevToolStack takes the opposite approach: every tool runs entirely in your browser. There is no processing backend, no upload endpoint, and no save feature. You can open your browser's developer tools, watch the Network tab, and confirm that formatting a document or decoding a token generates zero requests. The pages themselves are pre-rendered static files.

Principles

• Client-side always. If a tool can run in the browser, it must. Your data never leaves your device.
• Free with no gates. No accounts, no paywalls, no artificial limits, no "pro" tier.
• Fast by default. Static pages, no server round trips, results as you type.
• Honest tools. Each page documents what the tool actually does — including its limitations and edge cases.

Get in touch

Found a bug, or want a tool that doesn't exist yet? Send a message — every suggestion is read, and many of the tools on this site started as user requests. You can also read about how your data is handled in the privacy policy, or browse the full collection on the homepage.