How do I reduce the KB size of a JPEG?

To reduce the kilobyte (KB) size of a JPEG file, you can employ various methods depending on whether you prefer desktop applications, built-in features, or online converters. Here are the key approaches summarized from the provided sources:

Desktop Software Methods:

1. Resize and Optimize: Using image editing software such as Adobe Photoshop or Apple's Preview app on macOS, you can resize the image dimensions and adjust the resolution to decrease the file size. Additionally, you can explore online tutorials for similar actions within Microsoft's Photos app on Windows.

   • Photoshop: File → Open, then Image → Image Size. Maintain aspect ratio and adjust pixel dimensions accordingly. Optionally, modify the resolution and choose appropriate resampling methods like Bicubic Sharpener or Bicubic.
   • Preview on macOS: Open the JPEG, click Tools → Adjust Size, define new dimensions, and save the modified version.

2. Lossy Compression: Only lossy compression is applicable to JPEG files due to their inherent structure. Control the amount of compression to strike a balance between file size reduction and image quality preservation.

Online Converters and Services:

1. Browser-based Conversion: Utilize online services like Adobe Acrobat online to convert JPEG to PDF and then compress the resulting PDF before converting it back to JPEG. This approach helps maintain visual integrity while significantly decreasing the file size.

2. Online Image Resizers: Numerous online tools exist for resizing and compressing JPEG files directly, often allowing users to simply drag and drop their images onto the webpage. Examples include TinyIMG, Compress JPEG, and FreeConvert. These services analyze images and apply optimal strategies for compression, sometimes offering customizable parameters.

Remember that compressing a JPEG file involves tradeoffs between file size and image quality; therefore, carefully consider the acceptable levels of compression for your particular needs.