Rarely recommended for photos. Convert to GIF only if you need animation capabilities or are working with very old web systems. GIF's 256-color limit significantly degrades photo quality. For static images, keep JPG or use PNG for better results.
Yes, significantly. JPG photos contain millions of colors, but GIF only supports 256. This creates visible color banding and quality loss in photographs. GIF is designed for simple graphics and logos, not photos.
For photographs, no. JPG is superior for photos. GIF might be better for very simple graphics with few colors or if you need animation. For modern web use, WebP is better than both JPG and GIF for most purposes.
Not for photographs. Photo JPGs are usually more efficient than photo GIFs. GIF only becomes smaller for simple, flat-color graphics with minimal detail. Converting complex photos to GIF usually increases file size AND reduces quality.
Keep photos as JPG for best quality and file size. If you need transparency, use PNG. For modern web with animation needs, consider WebP which supports animation and provides better compression than GIF.