Use JPEG for dependable photo compatibility, PNG for exact pixels and transparency, WebP for a practical modern default, and AVIF when smaller delivery can justify slower encoding.

JPEG

JPEG is efficient for opaque photographs and universally understood. Repeated editing and saving can compound visible loss. It has no alpha channel.

PNG

PNG stores pixels losslessly and supports alpha. It excels for logos, interface captures, diagrams, and sharp text. Detailed photographs often produce large PNG files.

WebP

WebP supports lossy photos, lossless graphics, alpha, and animation. It is often the easiest modern format to adopt for mixed web content.

AVIF

AVIF can deliver excellent photographic compression and alpha. Encoding is significantly more CPU-intensive, so it is better as a deliberate output than an automatic answer to every upload.