Updated · Built and checked by the PlinzoTools team, formulas tested against published sources
Estimate an image's uncompressed bitmap file size from its pixel dimensions.
This is the raw bitmap size before compression. A saved JPG/PNG/WebP will typically be much smaller -- actual compressed size depends heavily on image content and quality settings.
This tool calculates an image's raw, uncompressed bitmap size in memory from its pixel dimensions and color depth (width × height × bytes per pixel). This is deliberately not an estimate of the final compressed file size (JPG, PNG, WebP) you'd get after saving -- actual compressed file size depends heavily on image content and compression settings, which this tool has no way to know in advance. Use this for understanding raw memory/canvas size, not for predicting a downloaded file's size on disk.
Enter the image's pixel width, height, and color depth (typically 24-bit for standard RGB, 32-bit with alpha transparency). The uncompressed size appears instantly, in both bytes and a human-readable unit.
The tool multiplies width by height to get the pixel count, multiplies that by the chosen color depth in bits, and divides by 8 to convert bits to bytes. The result is rounded to the nearest whole byte and then displayed in the largest sensible unit. The color depth menu offers three choices: 8-bit (256 colors), 24-bit true color RGB, and 32-bit true color with an alpha channel for transparency. The default is 24-bit.
Bytes = width × height × (bits per pixel ÷ 8)
Display units use 1,024 as the step. Values under 1,024 bytes show as B, values under 1,024 kilobytes show as KB with one decimal, values under 1,024 megabytes show as MB with two decimals, and larger values show as GB. If width or height is zero or less, the tool shows zero bytes.
A 1920 by 1080 image at 24 bits has 2,073,600 pixels, and each pixel takes 3 bytes, giving 6,220,800 bytes, which displays as about 5.93 MB. The same image at 32 bits takes 4 bytes per pixel, so 8,294,400 bytes, about 7.91 MB. At 8 bits it takes one byte per pixel, 2,073,600 bytes, about 1.98 MB. A hypothetical 4000 by 3000 photo at 24 bits is 12,000,000 pixels times 3 bytes, which is 36,000,000 bytes, about 34.33 MB of uncompressed data, even though a saved JPEG of it is typically far smaller.
This is the amount of raw pixel data needed to hold the image when fully decoded, with no compression and no file header overhead. That is roughly what a browser or image editor must keep in memory to display or edit a bitmap of that size (real software may allocate more or use a different internal format, so treat it as a lower-bound guide). It is not what your file will weigh on disk or how long a page will take to download. If you are sizing images for a website, this number is not the one to compare against a page-weight budget.
Formats like JPEG and WebP with lossy settings discard detail that is hard to see, and PNG applies lossless compression that exploits repeated patterns. A flat graphic with a few colors compresses dramatically. A noisy photograph compresses much less. Because compression depends on the content and the settings you choose, a general-purpose calculator cannot give an honest single figure. The only reliable way to know the final size is to save the image with your chosen format and quality and look at the file.
No -- compressed formats like JPG, PNG, and WebP can be dramatically smaller than the raw uncompressed size calculated here, and the exact result depends on image content and your chosen compression/quality settings, which vary case by case.
A standard RGB pixel has three channels (red, green, blue) at 8 bits each, totaling 24 bits or 3 bytes per pixel. The 32-bit option adds an 8-bit alpha channel for transparency.
No. It counts only the raw pixel data, calculated as width times height times bytes per pixel.
It steps by 1,024, showing bytes, then KB, MB, and GB depending on size.
Save it in the format and quality you intend to use and check the file size in your file manager or editor. That is the only dependable figure, since it depends on the image content.