Why JPEG Still Dominates in 2024

Photography went digital, social media swallowed the world, and storage got cheap enough to be essentially free, yet JPEG stubbornly remains the default image format for billions of people and devices. That persistence is not really a technical argument — by almost any objective measure, JPEG lost the format wars years ago.

WebP offers smaller file sizes at equivalent quality. HEIC, the format Apple quietly pushed onto iPhones in 2017, delivers roughly twice the compression efficiency of JPEG while preserving more detail. AVIF, backed by the Alliance for Open Media and drawing on video codec research, is better still.

JPEG was designed in 1992 for a world of dial-up modems and 256-color monitors, and its core compression algorithm, which works by carving images into eight-by-eight pixel blocks and discarding frequency data the human eye theoretically cannot detect, produces those characteristic smearing artifacts and blocky shadows that photographers have cursed for three decades. The format has known, well-documented, thoroughly solved limitations. And yet. The reason JPEG survives is the same reason QWERTY keyboards and the American penny survive: infrastructure inertia is a vastly more powerful force than technical superiority. Every camera manufacturer, every content management system, every legacy browser, every printing kiosk at every drugstore in America was built around JPEG at some point in the last thirty years, and that accumulated compatibility is worth more in practical terms than any compression algorithm.

When a grandmother sends a photo to her grandson, she is not weighing codec efficiency ratios — she is pressing a button and expecting it to work everywhere, on everything, without explanation. JPEG fulfills that promise with a reliability that newer formats are still earning. Developers who have tried deploying WebP or AVIF in production environments know the particular exhaustion of writing fallback logic for older browsers, of watching a perfectly optimized image render as a broken icon on some enterprise computer still running Internet Explorer eleven. There is also something quietly democratic about a format that requires no licensing fees, no decoder installation, and no technical knowledge to use. JPEG is not beloved, exactly, but it is trusted in the way that chipped municipal infrastructure is trusted — you complain about it constantly while quietly depending on it for everything.

The newer formats will eventually win. AVIF adoption is accelerating, Apple's ecosystem is nudging users toward HEIC whether they notice or not, and web performance demands are forcing the issue for anyone who cares about page load times. But the transition will take another decade at least, driven less by enlightenment than by the slow, unglamorous process of replacing old devices and old software one retirement cycle at a time.

JPEG will not go out with a bang. It will simply stop being the default one day, and most people will never notice it happened.