How Canvas Size Determines File Size
The uncompressed size of an image file is calculated precisely as width in pixels × height in pixels × bytes stored per pixel. RGB uses 3 bytes per pixel, RGBA (with transparency) and print-ready CMYK use 4 bytes, and grayscale uses just 1 byte. Multiplying by the number of layers gives a value close to the real size of layered files like PSD or AI.
How PNG and JPG Compression Is Estimated
PNG uses lossless compression, so its ratio varies a lot by content, but flat-color illustrations with fewer colors typically shrink to about 30-40% of the original. JPG uses lossy compression to produce much smaller files (about 5-10% of the original), but color edges can blur, which isn't ideal for crisp illustration artwork.
How to Use This Tool
Before sending a file to a client, or when your cloud storage is limited, check the estimated size here first so you can adjust your working canvas ahead of time. High-resolution print work in CMYK mode tends to be especially large, so make sure you have enough storage space reserved.
Frequently Asked Questions
A. Compression ratio varies a lot depending on color complexity, gradients, and noise in the image. This calculator provides an estimate based on typical averages.
A. Layered formats like PSD and AI store pixel data separately for each layer, so file size grows with more layers.
A. PNG usually produces smaller files for flat-color illustrations, while JPG is generally smaller for photo-like images with complex colors.