Compress Image

Three levels, and the one most people should use

Standard is the default and the right answer most of the time: quality 72%, which typically takes a phone photo down by well over half with nothing visible at normal viewing size. Light sits at 85% for images where detail genuinely matters — product shots, anything going to print. Aggressive drops to 55% and the loss is visible if you look; it is for when a hard size limit leaves no choice. If you want a specific number, the advanced section has a quality slider from 1 to 100.

The trick that beats compression: make it smaller

A 12-megapixel phone photo is about 4000 pixels wide. A full-width image on a website is rarely displayed above 1920, and inside a document it is often 800. Those extra pixels are pure file size that nobody ever sees, and no amount of quality tuning removes them.

That is what the Max Width control is for, and it is the single most effective setting on this page. Resizing 4000px down to 1920px removes roughly three quarters of the data before compression even begins, and the result looks identical wherever it is actually displayed. For web use, set 1920. For a document or an email attachment, 1280 or 800. Combine it with Standard quality and the saving is usually dramatic.

Why your PNG barely shrank

PNG and JPG compress in fundamentally different ways, and this catches people out. JPG throws away detail the eye does not notice, which works beautifully on photographs. PNG is lossless by design, so the only way to shrink one is to reduce how many distinct colours it stores — Standard reduces to 128 colours, Aggressive to 64. That works well for logos, icons, screenshots and flat graphics, which contain few colours anyway. It works poorly for photographs, which contain thousands.

So if you are compressing a photograph that happens to be saved as a PNG, tick Convert PNG to JPG. That single change usually does more than every other setting combined. Leave it off for anything that needs a transparent background, since JPG cannot store transparency.

Related tools

Resize Image changes dimensions precisely when you need an exact size rather than a maximum. Convert Image Format switches between formats, and JPG to PDF turns a set of finished images into a single PDF.