About LightUtils

LightUtils is a set of file tools that run entirely inside your browser. Compress a PDF, shrink a video, crop a photograph, clean up a recording, generate a QR code. The file you choose is read by the page, worked on by the page, and handed back by the page. It is never uploaded, because there is nowhere to upload it to.

Why it is built this way

Almost every free file tool on the web works by taking your file, sending it to a server, doing the work there, and letting you download the result. That is the easy way to build one, and it means your contract, your payroll spreadsheet, your family photographs and your voice recordings sit on somebody else's machine for a while. Most of those sites promise to delete them. You have no way to check.

Browsers can now do this work themselves. They can decode and encode video, read and write PDFs, resize images and hash text, all locally and fast. So we built the tools that way instead, and then made it checkable: open the Network tab and watch nothing happen. The security page explains exactly what does and does not leave your browser, and how to verify it without asking us.

How it is built

No frameworks and no runtime dependencies. Everything is plain JavaScript modules served from this domain: the PDF writer, the MP4 muxer, the Fourier transform behind the noise reducer, the ZIP writer and the AES-256 encryption are all written for this project rather than pulled from a package registry. That keeps the pages small and means there is no third-party code between you and your file.

The results are checked against software that has nothing to do with us. The PDFs are opened with Poppler and Chrome's PDF engine, the video with Chrome and Apple's AVFoundation, the audio with Apple's CoreAudio. A file that only our own code can read is not a file we are willing to hand anybody.

What it costs

Nothing, and there is no account to make. We intend to show advertising to pay for the domain and the time. Advertising will not change how the tools work: the files will still be processed in your browser and still never uploaded. If it ever changes what we can honestly claim, the security page changes with it, automatically.

We do not sell anything, we have no premium tier, and nothing here is a trial of something else.

Who makes it

LightUtils is built and operated by CODENIVERSE (opens in a new tab), a software company in Thailand. The site is bilingual because we are, and the plan is to add more languages as we can do them properly rather than quickly.

Something broken, or a tool you wish existed? Write to us on the contact page.