Image compressor.

Open any slow website and check what it weighs. Nine times out of ten the culprit is not the theme, the hosting or the plugins — it is a homepage carrying six megabytes of unoptimised photographs, each one a 12-megapixel original that a browser then shrinks to fit a 600-pixel box. The visitor downloads all of it and sees none of the detail.

Compression fixes the half of that problem that costs nothing. Combined with the resize control, it fixes both halves. A typical phone photo at 4.2 MB comes out around 280 KB at 1600px wide and 82% quality, and looks identical inside a web page. That is fifteen times less data on every single visit, on connections you do not control.

Run this before the upload, not after. Media libraries and CDN plugins can compress on the way out, but they cannot un-download the original from the visitor whose plugin cache missed, and they cannot give you back the disk space or the backup time. Compress at the source.

Worth knowing

• Aim under 200 KB for content images and under 400 KB for full-width hero images. Anything above that needs a reason.
• Resize first, compress second. Reducing dimensions removes data no compression can match.
• Screenshots and flat graphics keep their crispness better as PNG or WebP; JPG makes text edges fuzzy.