Free, fast, and private tools that run entirely in your browser.
NinjaFunction is a free collection of online tools built for developers, designers, students, and everyday users. We believe that the tools you use every day — encoding text, generating hashes, formatting JSON, creating passwords — should be fast, private, and accessible without signup, ads getting in the way, or data leaving your device.
Our mission is simple: build the fastest, most privacy-respecting utility tools on the web. Every tool on NinjaFunction runs entirely in your browser. That means:
NinjaFunction hosts a growing library of tools across several categories:
Most "free online tools" out there are neither free nor private. They bury the tool behind popups, force you to sign up, upload your files to unknown servers, or harvest your data for ads. We got tired of it — so we built the alternative.
NinjaFunction uses modern browser APIs like the Web Crypto API, Canvas, and WebAssembly to run everything locally. The result is a toolset that is genuinely free, genuinely private, and genuinely fast.
Every tool on NinjaFunction is built on the same principle: your data stays on your device. When you generate a hash, create a password, or format JSON, all the work happens in your browser's JavaScript engine. Nothing is transmitted to our servers. You can verify this by disconnecting from the internet before using any tool — most will continue to work perfectly.
Beyond tools, we publish beginner-friendly articles that explain technical topics in plain English. From "What is an API?" to "How to Install Odoo 19 on Ubuntu", our goal is to make technology approachable for everyone. Browse all articles on our blog.
NinjaFunction is maintained by a small team of developers and writers who use these tools daily in their own work. We build what we wish existed. Contributions, suggestions, and feedback from our users directly shape what we build next.
Because everything runs locally, there is very little data for us to protect — and that's exactly how we like it. We use Google Analytics for basic site statistics (page views, browser types) but never track what you do inside the tools. For full details, read our Privacy Policy.
NinjaFunction is free and always will be. There are no premium tiers, no hidden limits, and no signup walls. If you find the tools useful, the best way to support us is to share them with someone who might need them.
Have a question, found a bug, or want to suggest a new tool? We would love to hear from you. Please contact us — we read every message.
