How Byteshrink works
Byteshrink is a website that does all the work inside your own browser. Open it, add a file, choose your settings, and get a smaller version back. Nothing is uploaded and nothing is kept.
Step by step
Step 1
Your file opens on your device
When you add a file, it is opened straight from your computer or phone. It is never sent over the internet.
Step 2
Byteshrink reads it
The tool looks inside the file to work out its size, dimensions or page count.
Step 3
Your changes are applied
Any cropping, rotating or resizing you asked for is done to the picture.
Step 4
The file is rebuilt smaller
Byteshrink saves a fresh copy at the quality and size you chose. Extra hidden data is dropped along the way.
Step 5
You download the result
The finished file is handed straight back to you. Pick one file, or several bundled together.
Making images smaller
Photos, screenshots and graphics all work the same way.
Byteshrink opens your image, turns any crop or rotation you set into the final picture, and shrinks it down carefully so edges and detail stay as clean as possible.
It then saves a new copy. For JPEG and WebP you pick a quality level from 1 to 100 — lower means a smaller, softer file. PNG stays fully sharp unless you choose the colour-reduction option. Saving a fresh copy also clears out camera and location information.
Making PDFs smaller
You choose how far to go.
The strong option takes a fresh snapshot of every page at a resolution you choose and saves those snapshots as a new PDF. This shrinks scanned and picture-heavy documents the most, but the text becomes part of the image, so it can no longer be selected or searched.
The light option removes hidden document information and tidies up the file without changing any pages, so the text stays selectable.
Keeping things quick
Why it stays responsive even with big files.
The parts that do the heavy lifting only load when you actually open the tool, so the rest of the site stays fast.
Files are handled one at a time, with a progress bar for each, so your device is never overloaded and the page keeps working while it runs.
Still curious? The FAQ covers limits, quality and file types.