How to make a large image file smaller
Reduce image dimensions and adjust compression without uploading your original, and understand why some converted files get bigger.
File size and dimensions are different
Dimensions describe the width and height in pixels. File size is the number of bytes needed to store the image. Two pictures with the same dimensions can have very different file sizes. Changing the filename extension alone does not convert or compress the image.
1. Choose the image and output format
Open the converter and select the original. Try JPG for photos that need broad compatibility, or WebP for a web image. Keep PNG when transparent edges and sharp text matter more than minimum file size. The current converter accepts up to 100 MB per file and 120 megapixels, subject to device memory.
2. Resize for where the image will appear
Under Image size, choose a longest side such as 1,920 or 1,280 pixels, or enter a custom value. The converter keeps the proportions and does not enlarge smaller images. Automatic size is a safety setting: it only reduces images that exceed the output limits. It does not guarantee a small file suitable for a particular upload form.
3. Adjust quality and compare
For JPG, WebP or AVIF, choose File size, then Try a maximum file size, and enter a KB target per image. The tool tries up to eight quality settings down to 10% at your chosen dimensions. Each result reports whether it fits. If the target is missed, reduce Image size and try again. One target KB is 1,000 bytes. Open the download and inspect faces, text, edges and gradients before using it.
Why a converted file can be bigger
Saving a compact photo as PNG, BMP or TIFF can increase its size. A high quality setting can also produce a larger file without recovering any lost source detail. Start each new attempt from your original rather than repeatedly compressing already compressed downloads.
Large artwork and device memory
A 10,866 by 4,961 pixel image is about 54 megapixels. Automatic size reduces it to fit within 32 megapixels and 8,192 pixels per side. A compressed file can use much more memory when decoded. On a memory-limited device, try one image at a time and a smaller output size. This tool does not preserve source DPI or print color profiles.