About Kastavo

Kastavo brings together simple everyday tools — like unit converters, calculators and generators — in one place, with a fast, consistent experience across all of them.

Each tool is built to solve one specific task in a few seconds, without invasive ads, unnecessary steps, or requiring you to create an account.

Our mission is to build the most useful, trustworthy and accessible tools portal on the internet, and to do it sustainably over many years — not just shipping isolated tools, but building a coherent ecosystem of utilities and content.

We believe Kastavo's growth should be a consequence of the quality of what we offer, not the other way around.

All of Kastavo's tools run entirely in your browser. That means instant results, no waiting on a server, and the values you type never need to leave your computer or phone.

That's an intentional design principle: speed and privacy aren't an afterthought, they're part of how Kastavo is built.

Kastavo is just getting started. New tools, categories and content are added continuously, aiming to cover more and more everyday tasks — from technical conversions to utilities for developers, text, images and beyond.

Kastavo was built to be multilingual from day one. The site is currently available in Portuguese, English and Spanish, with units, number formats and content adapted to each language — and more languages may be added as the project grows.

Kastavo is maintained by Michel Davi, a developer based in Betim, Minas Gerais, Brazil, who creates, reviews and updates the site's tools and texts. The goal is for every tool to explain clearly how its result is calculated, so you can check it and trust what you see. The site is free and may be supported through advertising.