Image compression vs resizing: which should you use?
Compression and resizing both make image files smaller, but they solve different problems. The right choice depends on whether the image dimensions are already appropriate for where it will be used.
Resizing changes dimensions; compression changes encoding
Resizing changes the pixel width and height. A 4000×3000 photo resized to 1200×900 contains far fewer pixels, so the file can become dramatically smaller. Compression keeps the dimensions but encodes the image more efficiently or with lower quality. If an image is much larger than the display area, resizing usually gives the biggest reduction first.
A practical order for web images
Start by deciding the largest dimensions you actually need. Resize the image to those dimensions with the Image Resizer. Then use the Image Compressor if the file is still larger than you want. This two-step approach avoids throwing away quality while keeping thousands of pixels that will never be displayed.
JPG, PNG and WebP are not interchangeable
JPG is a strong choice for photographs because lossy compression can reduce size substantially. PNG is useful when you need transparency, crisp flat graphics or lossless storage, but photographs can become large. WebP can provide good compression for both photographic and transparent images in modern browsers. Use the Image Format Converter when a different format is more appropriate for the content.
How far should you lower quality?
There is no universal quality percentage. A detailed photograph can often tolerate moderate compression that a screenshot with small text cannot. Export a copy, view it at the size people will actually see it, and inspect edges, text and gradients. Stop when additional file savings produce visible artifacts that matter for the use case.
Privacy and metadata
Resizing or re-encoding an image can also change or remove embedded metadata. If metadata matters, inspect it first with the EXIF Metadata Viewer & Remover. Keep the original image if you may need camera details, timestamps or other embedded information later.