About

GlideConvert converts, compresses and resizes images, video, audio and PDF files without uploading them. Every conversion runs inside your own browser, on your own device.

Why we built it this way

Most online converters upload your files to their servers, process them there and send them back. That is slow for large videos, has upload limits, and means strangers’ computers hold copies of your photos, scans and recordings. Browsers have become powerful enough to do the work themselves — so we let them.

How it works

• Images are decoded and encoded with your browser’s built-in codecs, plus WebAssembly versions of libheif (HEIC), libwebp, libavif and MozJPEG where the browser lacks a codec.
• Video and audio use the WebCodecs API, which taps into your device’s hardware video encoder. Older formats (WMV, FLV, AVI and others) fall back to FFmpeg compiled to WebAssembly.
• PDF pages are rendered with PDF.js — the same engine that powers Firefox’s PDF viewer — and new PDFs are created with pdf-lib.

Because the files never leave your device, there is no upload wait, no queue and nothing for anyone to leak.

How we make money

The free version shows a few ads. GlideConvert Pro removes the ads and the batch and size limits. That is all — we do not sell data, and we could not even if we wanted to, because we never receive your files.

Contact

Questions, bug reports or a format you are missing? Write to hello@glideconvert.com.