How large is an image of a whole web page on a Mac?
9.26 MB at the median, and 2.26 MB after half size and new PNG compression, 82.9% smaller. Measured on October 28, 2026 on public web pages captured at Retina resolution, 2880 pixels wide: the images weighed 2.40 to 29.46 MB, and 0.54 to 3.11 MB afterwards.
How large is an image of a whole web page?
Between 2.40 and 29.46 MB: on October 28, 2026 the largest were pages with many photos, the MacBook Pro product page on apple.com at 29.46 MB and the nasa.gov home page at 28.42 MB. The text-heavy pages, the Wikipedia article on PNG and the MDN page on the img element, came to 12.12 and 6.39 MB.
At a window width of 1440 points, a whole page at Retina resolution is 2880 pixels wide and up to 40,000 pixels tall. A single MacBook Pro screenshot weighed 1.22 MB at the median in an earlier measurement, see How much smaller does a Mac screenshot get?.
How much does half size save?
Halving the edge length saves 41.9% at the median, between 26.5% and 67.7% for the pages on October 28, 2026. Pages with photos gained the most (64.3% and 67.7%), pages with text the least (26.5% and 27.7%).
How much does PNG compression save?
Compression with pngquant followed by oxipng saves 63.7% at the median, between 59.4% and 69.4%. For the nasa.gov home page it saved slightly less, 66.6%, than half size alone at 67.7%.
How pngquant and oxipng work on their own is covered in How much can you compress a PNG on a Mac?.
How much do both steps save together?
Both steps together make an image of a whole web page 82.9% smaller at the median, from 9.26 to 2.26 MB. Photo pages got about 90% smaller, text pages 71.7% to 77.6%.
| Page | Content | PNG | Half size | Compression | Both |
|---|---|---|---|---|---|
| Wikipedia, PNG | Text | 12.12 MB | 8.76 MB | 4.61 MB | 3.11 MB (−74.3%) |
| MDN, img | Text | 6.39 MB | 4.69 MB | 2.60 MB | 1.81 MB (−71.7%) |
| GitHub, oxipng | Interface | 2.40 MB | 1.69 MB | 0.91 MB | 0.54 MB (−77.6%) |
| Apple Support, screenshot | Interface | 4.51 MB | 2.06 MB | 1.56 MB | 0.54 MB (−88.1%) |
| apple.com, MacBook Pro | Photo | 29.46 MB | 10.52 MB | 9.02 MB | 2.87 MB (−90.2%) |
| nasa.gov, home page | Photo | 28.42 MB | 9.19 MB | 9.51 MB | 2.72 MB (−90.4%) |
In brackets, the saving compared with the PNG.
How do you capture a whole web page on a Mac as one image?
Levati captures a whole page from Chrome or Safari, scrolls it by itself, stitches it into one image up to 20,000 points long and then does both steps on its own: half size, on by default, and new compression with pngquant and oxipng. The image lands on your desktop or the clipboard.
For this measurement the pages were captured without Levati, in a browser without a window, so that nothing had to happen on screen.
How was this measured?
Six public web pages were measured on October 28, 2026 on a MacBook Pro with M5 Pro running macOS 27.2.
- Capture: Chromium 156 through Playwright 1.64.1 without a window, window width 1440 points, double pixel density as on Retina, the whole page after scrolling once to the end so that lazy images appear; saved as PNG.
- Length: at most 20,000 points, as in Levati; the pages from Wikipedia (23,293 points), MDN (22,421) and apple.com (34,849) were cut there.
- Pages: Wikipedia, PNG, MDN, img, GitHub, oxipng, Apple Support, screenshot, apple.com, MacBook Pro and nasa.gov, all opened on October 28, 2026.
- Half size: with macOS
sipsto half the edge length, saved as PNG at 72 dpi. - Compression: the Levati command-line tool, which runs pngquant 3.0.3 with
--skip-if-largerfollowed by oxipng 10.2.1; once on the full PNG and once on the halved one. - Analysis: file size in bytes, median and range from minimum to maximum; 1 MB is 1,000,000 bytes.
Not measured: captures from Safari or Chrome with a window, other window widths and image quality. Chromium saves PNG with its own encoder, so a capture with screencapture can differ in size. The page captures themselves are not published.