刻，为东亚传统时间单位，由于长度对应英语的Quarter（即1/4，粤语音译为骨打，后又简称为骨），现代指四分之一个小时，即15分钟。

刻，在中国古代已是时间单位，多由漏刻计时。

隋后普遍行百刻制，每天一昼夜为100刻，即一刻为14.4分（14分24秒）。如在许慎的《说文解字》中说到「漏以铜壶盛水，刻节，昼夜百刻。」但因100不能被12（一天的时辰数）整除，后来一昼夜又被先后改为96、108、120刻。

至顺治二年（公元1645年）颁行时宪历后，改为日96刻，每时辰八刻（初初刻、初一刻、初二刻、初三刻、正初刻、正一刻、正二刻、正三刻）。自此每刻15分，无「四刻」之名。

The ke (Chinese:刻; pinyin:kè) is a time unit in traditional China. The ke is the extension of the scale on the sundial or the rule of the water clock. In French decimal time, ke is equivalent to 10 decimal minutes, sometimes called a décime.
The major ke is 14.4 minutes (14 minutes 24 seconds), which is the time between two centiday scales, and the minor ke is 2.4 minutes (2 minutes 24 seconds), which is the common factor time between centiday scale and shi scale. It was customary to subdivide the minor ke into 10 fen (Chinese:分; pinyin:fēn), just as cun and mace; thus the major ke is divided into 60 fen.