About this site

One job, done in depth: making a picture file smaller — to a quality, a cap or a form's published spec — and saying exactly what it cost.

Why only that

Most tools in this category are a menu. You arrive wanting a file under 50 KB and are offered eleven things, none of which is quite that. The narrower alternative is to take one job seriously — every format that job touches, every edge case it runs into, every reason it fails — and to say so plainly when the job cannot be done.

So this site compresses — and does the jobs that sit right next to compression when a form or a page sets the rules: fewer pixels when the pixel count is the problem, a photograph or signature fitted to a published upload spec, a check of what a file really is before you upload it, and metadata removed without re-encoding. It does not convert between formats as a goal and it does not edit pictures. Every one of those jobs runs on this device.

How the numbers here are arrived at

• Every size printed is a real file. Nothing is estimated, extrapolated or scaled from a preview — the byte count beside a row is the length of a blob that already exists in memory.
• The comparison at 400 percent decodes the actual output. What you magnify is the file you download, not a rendering of what it might look like.
• The metadata figures are segment lengths read out of your file, not typical values from a table.
• When a run cannot do what was asked, the number reported is what it managed, labelled as such.

What it will not do

It will not resize a picture to reach a byte target without asking first, it never carries GPS or a thumbnail through a re-encode (the colour profile, date and credit, XMP and IPTC only when you ask), and it has no perceptual metric and therefore offers no automatic mode. Its encoders — MozJPEG, libwebp, libavif, OxiPNG — run as WebAssembly in your browser, and when one cannot load the browser's own writer stands in, which the result says. Each of those is stated where it matters rather than only here.

Who keeps it

A small independent team that builds single-purpose picture tools on the web. There is no account system, no newsletter and nothing to sign up for. Corrections and bug reports are welcome — the exam-portal figures in particular need to be checked against real forms every cycle, and that is the part most likely to drift.

Start here

• Compress an imageThe tool, with all three mechanisms and the file queue.
• Compress to a size in KBIf you arrived with a number from an upload form.
• PrivacyWhat this page reads, what it never sends, and how measurement works.