Chrome's own screenshot tool only captures what fits on screen, so a long page gets cut off. A full page screenshot extension scrolls through the whole page automatically and stitches it into a single image, which is faster than taking several screenshots and pasting them together by hand.
How a full page screenshot extension works
After you click the toolbar icon, the extension scrolls the page from top to bottom, capturing each section and combining them into one tall image. This handles dynamic content like sticky headers and lazy-loaded images better than manual screenshots, since it waits for each part of the page to render before moving on.
Saving and exporting your screenshot
Most screenshot extensions let you save the result as a PNG or PDF, copy it to the clipboard, or open it directly in an editor. PDF export is useful for long articles or receipts you want to file away, while PNG suits sharing a single image in a chat or a bug report.
When you don't need an extension
Chrome DevTools has a built-in full page screenshot option under the command menu, reached by pressing Ctrl+Shift+P or Cmd+Shift+P and typing capture full size screenshot. An extension is worth adding when you take these screenshots often and want a one-click toolbar shortcut instead.