Image compression guides

The honest answer is: more than you think.

Colours that look vivid on your camera can look dull after upload if profiles are mishandled.

Yes, but how much depends on your settings.

Mac users can compress JPEGs without opening Preview or Photoshop.

Resizing is the single biggest lever for file size.

Getting a JPEG ready for landing pages is mostly about two numbers: pixel width and file size.

Many online compressors upload your images to a server. That is not always necessary.

Image compression comes in two flavours.

Speed is the most visible benefit of compression.

Blurriness after compression usually comes from resizing too far, not from JPEG itself.

Strictly speaking, JPEG compression always discards something, but you can make the loss invisible.

Resizing is the single biggest lever for file size.

There is no single magic number, but there is a sensible range for resume and CV photos.

Size limits are written in kilobytes and megabytes, and the units trip people up.

Image compression comes in two flavours.

You do not need paid software to compress images well.

Blurriness after compression usually comes from resizing too far, not from JPEG itself.

When you have dozens of images, consistency matters as much as size.

A few habits cause most of the blurry or oversized images we see.

Quality is the slider people touch first, yet it is often the least understood.

Aspect ratio is the shape of the image, and the wrong one leads to awkward crops.

Text inside photos, like signs or slides, needs a gentler touch.

Screenshots behave differently from photos.

Photos carry hidden metadata such as camera model, date and sometimes GPS location.