Kastavo

What it is

Kastavo brings together simple everyday tools in one place with a fast, consistent experience. Each tool is built to solve one specific task in a few seconds without invasive ads, unnecessary steps, or requiring account creation.

All tools run entirely in your browser, meaning instant results with no server waiting and values never leaving your computer. The site is currently available in Portuguese, English and Spanish, with units and formats adapted to each language.

Kastavo is maintained by Michel Davi, a developer based in 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.

Questions from the bench

Is Kastavo free?

Yes, every tool is free with no sign-up and no hidden limits. To keep the site running, it may display ads, but using the tools does not require payment or an account.

Are my files and text sent to a server?

No. The tools run entirely in your browser; files, text and values are processed in your device's memory and are not sent to Kastavo's servers. Your content never travels to the server.

Do the tools work offline?

Most tools work offline once the page has loaded. However, eleven tools including Extract Text from Image, Split PDF, and various PDF converters require an internet connection the first time you use a feature to download necessary components.

Does Kastavo collect any data about me?

No data is collected from the content you process in the tools. The site uses Google Analytics if you accept cookies to measure visits in aggregate, and uses cookies or local storage to remember preferences like language and theme. See the Privacy Policy for details.

Which browsers are supported?

Any modern browser such as Chrome, Edge, Firefox and Safari with JavaScript enabled on desktop, tablet or mobile. Some tools using recent browser features may not be available in older versions.