Image Compressor

Nothing is uploaded

This matters more than the compression does. Every free image compressor that asks you to upload a file receives that file — a photo of a passport, a payslip, a medical form, a child. This page never sends it: your browser decodes the image, redraws it at the size you asked for and encodes it again, all on your own machine.

That claim is worth nothing unless it is checked, so it is: the test suite for this page records the requests this tool makes while an image is processed and fails if one of them could carry the file. The page around the tool loads Cloudflare's analytics script, which counts the visit and never sees the picture; the privacy page lists what it reports.

How to use it

1. Choose a JPEG, PNG or WebP.
2. Set the quality. 75 is a good starting point and rarely looks different.
3. Cap the longest side if the dimensions are the real problem — a 4,000-pixel photo in a form that displays it at 800 is mostly wasted bytes.
4. Press Compress, check the result, and download it.

The three formats behave differently

This is one tool rather than three, because the file you happen to have does not change the work. What changes is what compression means:

• JPEG is lossy. The quality setting decides how much detail is discarded, and the loss is permanent. Best for photographs.
• PNG is lossless. It never discards detail, so a quality setting would be meaningless and the slider is switched off. A PNG shrinks mainly by reducing its color palette or by a stronger lossless compressor, and a browser canvas offers neither — so re-encoding a PNG as PNG often makes it bigger. Save it as WebP instead.
• WebP is lossy like JPEG but roughly a quarter to a third smaller at the same visual quality, and it keeps transparency. It is the right answer for most files today.

When the result is bigger

It happens, most often with an already-optimized PNG, and it is the point at which this kind of tool usually lies: it shows a new file size, calls it a result and lets you download something worse than what you started with. This page says the file grew, by how much, and suggests what to do instead.

What this does not do

It does not crop, rotate or edit, and it does not process several files at once. It also does not keep metadata: your browser writes the new file from the pixels alone, so location, camera and date details in the original are not carried into the copy you download — the test suite checks that a location written into a file does not come out the other side. Keep the original if you need them.