Compare JPEG Image and Bitmap Image formats — understand the key differences and when to use each
JPEG Image
JPG (also known as JPEG — Joint Photographic Experts Group) is the world's most popular image format for photographs and web images, first standardized in 1992. JPG uses DCT-based lossy compression to reduce file sizes by 90% or more while maintaining visual quality that's often indistinguishable from the original. The format supports up to 16.7 million colors (24-bit color depth), making it ideal for photographs, gradients, and complex imagery. JPG compression levels are adjustable: higher compression means smaller files but more artifacts, while lower compression preserves quality at larger sizes. JPG does not support transparency or animation. It's the default photo format for digital cameras, smartphones, and web browsers. Common use cases include website images, email attachments, social media posts, and print materials. For web optimization, JPG images should typically be compressed to 60-85% quality.
Bitmap Image
BMP (Bitmap Image File) is an uncompressed raster image format developed by Microsoft. BMP stores pixel data directly without compression, resulting in very large file sizes but perfect image quality with zero artifacts. The format supports 1-bit (monochrome), 4-bit (16 colors), 8-bit (256 colors), 16-bit, 24-bit, and 32-bit color depths. BMP is primarily used in Windows environments and was historically the default format for Windows Paint. While BMP offers the highest quality preservation, its lack of compression makes it impractical for web use or email. Converting BMP to PNG provides identical visual quality with dramatically smaller file sizes. BMP does not support transparency, animation, or metadata. It remains useful for certain technical applications and as an intermediate format in image processing pipelines.
| Feature | JPG | BMP |
|---|---|---|
| Full Name | JPEG Image | Bitmap Image |
| File Extension | .jpg | .bmp |
| Category | image | image |
| Free to Convert | ✓ Yes | ✓ Yes |
| Browser Support | ✓ All Browsers | ✓ All Browsers |
| Convert to Each Other | ✓ Yes | ✓ Yes |
或将文件拖放到此处
最大文件大小：2GB