Dong Ho Dem Nguoc Online: Huong Dan Tung Buoc
Cong cu Countdown Timer Online dem nguoc tu bat ky khoang thoi gian nao ban nhap bang phut va giay. Huong dan nay noi ve cach dat thoi gian, nut Start, Pause va Reset thuc su lam gi, va nen mong doi - va khong nen mong doi - dieu gi khi bo dem ve den khong.
Last reviewed: 2026-07-02
freetoolonline.com Editorial TeamDat thoi gian
Hai o so dieu khien bo dem: Minutes (0-999) va Seconds (0-59). Trang mo len voi gia tri mac dinh la 5 phut 0 giay. Nhap gia tri moi vao mot trong hai o va man hinh cap nhat ngay, ngay ca truoc khi ban nhan Start, de ban co the xac nhan thoi gian dung truoc khi bo dem bat dau.
Start, Pause va Reset
Start bat dau dem nguoc: man hinh giam mot giay mot lan, moi giay mot lan, cho den khi ve 00:00. Pause dung bo dem dung tai vi tri hien tai ma khong mat thoi gian con lai - nhan Start lai se tiep tuc tu diem do thay vi bat dau lai. Reset dung bo dem va dua man hinh tro lai thoi gian dang co trong hai o Minutes va Seconds.
| Cai dat | Pham vi / gia tri | Ghi chu |
|---|---|---|
| Minutes | 0-999 | So phut nguyen; cong voi Seconds de ra tong thoi gian |
| Seconds | 0-59 | Cong voi Minutes x 60 de ra tong thoi gian |
| Thoi gian mac dinh | 5 phut 0 giay | Hien thi khi tai trang, truoc khi ban thay doi gi |
| Toc do cap nhat | Moi giay mot lan | Man hinh cap nhat moi 1.000 mili giay khi dang chay |
Dieu gi xay ra khi ve den khong
Khi man hinh ve den 00:00, bo dem tu dung lai va thong bao "Time is up!" xuat hien ben duoi. Do la dau hieu duy nhat trang nay dua ra - khong co am thanh, chuong bao hay thong bao he thong, vi vay neu ban khong nhin vao tab thi co the bo lo luc bo dem ket thuc. Reset xoa thong bao va dua man hinh tro lai thoi gian trong o Minutes/Seconds, san sang chay lai.
Dong ho dem nguoc so voi cac cong cu dong ho
Cong cu nay dem nguoc ve khong tu thoi gian ban chon. Cac cong cu di kem dong ho so va dong ho kim hien thi gio hien tai va tu cap nhat lien tuc, khong co nut Start/Pause/Reset va khong co thoi gian muc tieu. Dung dong ho dem nguoc khi ban quan tam den thoi gian con lai; dung cac cong cu dong ho khi ban quan tam den gio trong ngay.
Cac cach dung pho bien
Nguoi dung dung bo dem nguoc tren trinh duyet cho mot buoc nau an, mot khoang tap luyen, mot bai thuyet trinh hoac muc chuong trinh co gioi han thoi gian, mot bai kiem tra hoac phan thi co tinh gio, hoac mot loi nhac nghi ngan don gian - bat ky noi nao mot bo dem nhanh, khong can cai dat, de dung hon so voi tim dien thoai hoac dong ho bam gio bep vat ly.
Cong cu nay khong lam gi
No khong phat am thanh, khong rung, va khong gui thong bao trinh duyet hoac he thong khi het thoi gian - chi co thong bao tren man hinh thay doi. No khong tiep tuc dem trong nen: dong tab, hoac chuyen sang trang khac, se dung bo dem hoan toan, vi khong co tien trinh nen hay service worker giu no hoat dong. No cung khong luu bo dem dang chay giua cac lan truy cap, va trang nay chi theo doi mot bo dem tai mot thoi diem.
Quyen rieng tu
Bo dem nguoc chay hoan toan trong tab trinh duyet cua ban. Khong co gi ban nhap vao o Minutes hoac Seconds duoc gui di dau, khong can tai khoan, va trang khong lien lac voi server nao trong khi bo dem dang chay.
Cong cu lien quan
- Countdown Timer Online - cong cu chinh.
- Digital Clock Online - man hinh HH:MM:SS lon, truc tiep cua gio hien tai, khong phai bo dem nguoc.
- Analog Clock Online - cung gio truc tiep do tren mat dong ho co kim quay.
- Trang cong cu tien ich - cac cong cu chuyen doi va tao noi dung hang ngay khac tren trang nay.
Cau hoi thuong gap
Bo dem co phat am thanh khi ket thuc khong?
Khong. No chi hien thong bao "Time is up!" tren man hinh - khong co am thanh, chuong bao hay thong bao he thong.
Toi co the tam dung va tiep tuc ma khong mat thoi gian con lai khong?
Co. Pause dung bo dem dung tai vi tri hien tai; nhan Start lai se tiep tuc tu chinh thoi gian con lai do thay vi bat dau lai.
Bo dem co tiep tuc chay khong neu toi chuyen tab hoac dong trinh duyet?
Chuyen tab khong lam dung bo dem - bo dem van chay khi tab nay con mo. Dong tab, hoac dong trinh duyet, se dung bo dem hoan toan, vi khong co tien trinh nen.
Toi co the chay nhieu hon mot bo dem cung luc khong?
Khong the tren mot phien ban duy nhat cua trang nay - trang chi theo doi mot bo dem tai mot thoi diem. Mo trang trong tab hoac cua so thu hai neu ban can hai bo dem doc lap chay cung luc.
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