klevi.hu
Quizzes, tools and games, free and without ads or trackers.
- type
- Personal project
- my role
- Idea, design and development
- technology
- HTML, CSS, JavaScript
- live site
- klevi.hu
Starting point
Most Hungarian-language calculators and small tools are full of ads and trackers, often ask for registration, and load slowly on mobile. klevi.hu is the opposite: small, fast pages that do one thing and do it properly. Free, no registration, no ads and no tracking.
What is on it
Currently 18 tools, games and quizzes in five areas:
| Area | Examples |
|---|---|
| Finance | Salary calculator with the 2026 Hungarian tax rules and allowances, government bond calculator with real ÁKK rates, forint value calculator with the KSH price index since 1960 |
| Everyday tools | Name day finder with almost 3000 names, QR code generator with PNG and SVG download, password generator with exact bit strength, licence plate decoder |
| Games | Hungarian Wordle where CS, GY and SZ count as one letter; Snake; Minesweeper |
| Quizzes and history | Igazmagyar, How many camels are you worth?, Trianon 1920 with a map and sourced figures |
| Developer notes | Vue 3 notes with 20 recipes, a Git and GitHub handbook with a command search |
On the home page every page can be searched with Ctrl+K, and favourites, recently opened pages and game records show up there too.
Decisions
No framework. Plain HTML, CSS and JavaScript. Every page loads only the code its tool needs, so it opens quickly even on a slow mobile connection.
Everything runs in the browser. Calculations happen on the visitor’s device and no data goes to a server. Favourites and records are stored only in that browser, and there are no cookies.
A strict content security policy. The site’s Content-Security-Policy only allows scripts, styles, images and fonts from its own domain. If an external script ever slipped in, the browser would not run it.
Hungarian specifics. The Wordle treats Hungarian two-character letters as one, the salary calculator follows the current tax rules, and the finance tools work with KSH, MNB and ÁKK data.
Where it is now
klevi.hu keeps growing and is currently at version 2.7. New tools follow the same rules: one task, fast loading, and no data leaves the device.