How Localvert handles your data: a plain-language explanation

When you drop a file into Localvert, your browser reads it into memory and converts it with code that runs on your own processor — Canvas for images, WebAssembly builds of FFmpeg for video and audio, pdf.js, pdf-lib and qpdf for PDFs. There is no upload step, and we have no server that could receive a file.

Because nothing is uploaded, there is nothing for us to delete afterwards and nothing that could leak from our side. You can check this yourself with the offline test or the browser's Network tab.

Two small things: the language you picked and, if you buy premium, your licence key. Both live in your browser's local storage, never leave your device, and disappear if you clear your browser data.

Our hosting provider (Cloudflare) delivers the pages to you, which means it processes your IP address like any web host. Google AdSense shows the ads and uses cookies for that; you can turn off personalised ads in Google's Ads Settings. Video conversion downloads the open-source FFmpeg engine from the jsDelivr CDN. Text recognition downloads the open-source Tesseract engine and language data the same way. Speech to text downloads the Whisper model from Hugging Face the first time. If you activate a premium licence, the key — and only the key — is sent to Lemon Squeezy to check it is valid.

None of these services receive your files.

We don't run analytics, tracking pixels or fingerprinting. There are no accounts, so we have no email addresses, passwords or usage history. That also means we can't tell you how you used the site — we simply don't know.

Open a Localvert page and convert one file while online, so the browser has downloaded the code that feature needs. Then switch your device to airplane mode and convert another file: it keeps working, because everything runs on your device. Some features — video, HEIC and PDF tools — load their engine the first time you use them, which is why the first conversion happens online.

On a computer you can also open the browser's developer tools and watch the Network tab during a conversion. You will see requests for page code and, when ads are shown, for advertising — but no request carrying your file.

Some features, such as converting very large videos on slow phones, would be easier with a server. If we ever add one, it will be a separate, clearly labelled option, the privacy policy will be updated first, and browser-only conversion will remain the default. We would rather not offer a feature than quietly start uploading files.

The files people convert are often personal: ID scans, contracts, photos of children, medical letters. Uploading them to convert a format is a risk that is simply unnecessary now that browsers are powerful enough to do the work themselves.