Which image format is generally preferred for web use due to smaller file sizes?

The preferred image format for web use, particularly when considering smaller file sizes, is JPEG. This format employs lossy compression, which means that it can significantly reduce the file size of images, especially those containing many colors or complex graphics, such as photographs. The compression method effectively removes some image data that the human eye is less likely to notice, leading to smaller file sizes without compromising visual quality to a noticeable degree.

JPEG images are particularly advantageous for web use since faster load times can improve user experience and SEO performance. The flexibility of JPEG in balancing image quality and file size is why it is widely used on websites, especially for photo galleries, product images, and other visually rich content.

In contrast, other formats like GIF and PNG are often larger in file size for more complex images. GIF is limited to a maximum of 256 colors, which may not be suitable for photo-like images, while PNG, although it supports transparency and has lossless compression, tends to create larger files compared to JPEG. BMP files are generally uncompressed, leading to even larger sizes, making them impractical for web use. Hence, JPEG is the preferred choice for achieving smaller file sizes while maintaining acceptable image quality on the web.