Estimate the uncompressed file size of an image from its dimensions and color depth. Includes JPG/WebP/PNG estimates — 100% free.
Enter dimensions to calculate size, or upload an image to auto-fill.
Drop an image here or use the upload button.
Enter the image width and height in pixels and choose a bit depth. The calculator works out the theoretical pixel-data size before compression and reports the image’s megapixel count. This is not the same as the size of a saved JPG or PNG: the calculation does not include file headers, metadata, row padding, or compression.
Without an uploaded image, the calculator does not claim to predict a compressed file size. Dimensions alone cannot provide a reliable JPG, WebP, or PNG estimate. A detailed photograph and a flat illustration at the same dimensions can compress very differently.
Upload a supported image and set the dimensions you want to evaluate. The tool creates local samples at those dimensions: JPG at 85% quality, WebP at 80% quality, and lossless PNG. It then shows the resulting sample sizes. The image is processed in your browser rather than uploaded to the site. These values reflect the displayed settings; another encoder or quality level may produce different results.
For an existing file you want to make smaller, try the Image Compressor. To change a file’s format, use the Image Format Converter or the JPG to WebP Converter.
It can help when preparing assets for a website, checking social-media dimensions, or estimating the memory needed for pixel data before compression. If you are preparing an image for print rather than the web, use the Image DPI Calculator to understand how pixel dimensions relate to a chosen print size.
No. The main result is a theoretical estimate of uncompressed pixel data for the selected bit depth. After an image is uploaded, the JPG, WebP, and PNG figures are measured from sample files encoded by the browser using the settings shown.
Compression depends on image detail, texture, color variation, noise, and encoder settings—not just width and height. An actual image is needed to produce a useful sample comparison.
No. Calculating and comparing formats does not replace the original file. Use the Image Resizer to change dimensions or the Image Compressor to reduce an existing file’s size.