How do animated GIFs affect performance?

Animated GIFs affect performance primarily through file size. Each frame is essentially a separate image-a 30-frame animation at 500x500 pixels can easily exceed 2-3MB, dragging down email load times dramatically.

Performance factors: Frame count-fewer frames, smaller file. Dimensions-resize before animating. Color depth-GIFs support 256 colors max; fewer colors = smaller files. Optimization-tools like ezgif.com can reduce size significantly. Looping-infinite loops don't affect file size but can annoy users.

Every frame costs bandwidth. A hero GIF that's 3MB makes your email painfully slow on mobile. Aim for GIFs under 500KB where possible; under 200KB is better. If your animation requires megabytes to look good, consider whether it's worth the performance cost, or link to video instead.