About
A growing collection of fast, private, no-signup online tools: word counter, password generator, QR code, JSON formatter, BMI, unit converter, and more.
Mission
Arnaud.app is a growing collection of small online tools that solve everyday problems without asking for your email, your data, or your attention. The pitch is simple: open the page, do the thing, close the tab. No accounts, no popups, no upsell, no seven-day trial that bills your card on day eight. It spans calculators, converters, text and developer utilities, design helpers and generators - and every one exists because someone needed it and got tired of the alternatives being slower, ad-laden, or stuck behind a signup wall.
Principles
Private by default
Most tools run entirely in your browser. Your data never leaves your device.
Fast
Static pages, instant results. No spinners, no upsells, no popups.
Free, no signup
No account, no paywall, no watermark. Just tools.
Privacy in practice
Pageviews are tracked via Umami Cloud (cookieless, aggregate) and Core Web Vitals via Vercel Speed Insights. Neither sees the text, files, passwords or JSON you paste into a tool. There are no third-party trackers, no advertising pixels, no fingerprinting scripts. The only cookies the site sets are your language choice and your theme choice - and only when you actually change them.
How it's built
The site is a Next.js 15 app written in TypeScript, styled with Tailwind CSS, and statically pre-rendered in five languages. Most tools run entirely in your browser using standard web APIs - Web Crypto for randomness and hashing, Intl for locale-aware formatting, Canvas for image and colour work - so nothing is uploaded unless a tool explicitly says otherwise. Static hosting keeps the cost and carbon low: a typical page weighs under 200 KB, a fraction of the ad-laden pages it competes with.
What's next
The catalogue grows in response to what people actually search for. Recent work added a full set of design tools (colour, gradient, box-shadow, contrast and clip-path generators), an in-browser image-conversion suite, currency-pair pages for the most-traded rates, and a native rewrite of the French, Spanish, German and Portuguese copy. Next up: more developer and design utilities, richer worked examples on each tool, and whatever comes up most in feedback. If something you'd find useful is missing, it's probably worth adding - so say so.
Built for the open web.