Format lab

Each picture below is the same source saved in a different format. The small window under each one magnifies a region so the differences show. The numbers are the files' real sizes in bytes.

Magnify

A photograph: the daisy, 800 × 533

Lossy formats win by a factor of ten or more. Compare the magnified petal edge: JPEG's blocks, GIF's dither dots, PNG's exact (and enormous) copy.

Photograph: Macro flower wallpaper, Free Nature Stock, CC0.

Flat colors and sharp edges. The JPEG has no transparency, so it carries a white box; on a dark page it shows. The SVG stays sharp at any magnification.

A chart: text and flat bars, 800 × 450

Few colors, long flat runs and small text. Look at the title through the magnifier: JPEG smudges every letter, and the last JPEG, squeezed to the PNG's size, falls apart.