> For the complete documentation index, see [llms.txt](https://javascriptuse.gitbook.io/javascript/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://javascriptuse.gitbook.io/javascript/creating-a-countdown-timer-ok.md).
# Creating a Countdown Timer, dakhoathienhoa.com.vn (oK)
### Ví dụ 1:
```html
Document
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### Ví dụ 2:
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Hoặc
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