> For the complete documentation index, see [llms.txt](https://krjaeh0.gitbook.io/j-log/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://krjaeh0.gitbook.io/j-log/programming/cs_basics/web_technologies/browser-and-devtools/devicetoolbar.md).

# DeviceToolbar

디바이스 툴바(Device Toolbar)를 활용하면 현재 브라우저의 화면 비율 및 User-Agent를 원하는 값으로 변경할 수 있습니다.

현대에는 웹에 접속하는 장치가 데스크톱, 태블릿, 스마트폰, 노트북 등으로 다양해지고 있으며, 웹 페이지가 렌더링되어야 할 화면 비율도 가지각색으로 많아지고 있습니다. 개발자는 모든 이용자에게 좋은 웹 경험을 줘야하므로, 자신이 개발한 웹 서비스가 다른 장치에서도 잘 작동하는지 점검해봐야 합니다. 디바이스 툴바를 이용하면 이러한 점검을 쉽게 진행할 수 있습니다.

![](/files/d696438fe2217bd969861f9b4eb0ef81ef3d59cb)


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