Measuring Food on Shabbos or Yom Tov
Question: Is it permitted to use a measuring cup or spoon to measure ingredients that will be used in a dish to be served on Shabbos or Yom Tov?
Discussion: Chazal considered all forms of weighing or measuring to be a weekday activity that should be restricted on Shabbos and Yom Tov.74 It is therefore forbidden to weigh oneself or measure one’s height,75 to hang a thermometer outdoors in order to determine the temperature, or to measure the size of a room with a tape measure.76
When it comes to measuring food items, however, Chazal were concerned about our oneg Shabbos and Yom Tov and were a bit more lenient, allowing measuring for the sake of assuring the quality of the food. If, for instance, a particular food would not be so tasty unless it was prepared exactly as the recipe specifies, such as a dressing that must be spiced or flavored just so, then it is permitted to use a measuring spoon or cup77 to measure those ingredients precisely.78 It is forbidden, however, to use a measuring cup to measure foods where a little more or a little less of an ingredient will not affect the overall taste and quality of the dish, such as a pasta salad or a rice pilaf, where having more or less pasta or rice will hardly make a difference to the taste of the finished product.79 It is permitted to use a measuring cup or spoon if it is used for approximation and not for measuring an exact amount.80
Measuring for Mitzvah Purposes
Question: Is it permitted to measure or weigh things on Shabbos or Yom Tov for the purpose of a mitzvah?
Discussion: Yes, it is. Since measuring and weighing were restricted by Chazal as a weekday activity, the restriction is lifted when the measuring81 or weighing82 is done for the sake of a mitzvah. It is therefore permitted to measure or weigh:
- a cup, to see whether it is large enough to be used for Kiddush or the Four Cups on Pesach.
- the amount of matzah that is required to fulfill the mitzvos of the Seder.
- the amount of food an ill person may eat on Yom Kippur.
- medicine (or food) for an ill person or a baby, since taking care of one’s health is considered a mitzvah.83
- a person’s body temperature to check for fever. (Unless the patient is dangerously ill, a digital thermometer may not be used.)
- the distance of 2000 amos from the end of the city to determine where techum Shabbos ends.
Although as stated the basic halachah is that it is permitted to weigh things on Shabbos for a mitzvah purpose, it is however correct to weigh it before Shabbos where possible.84
74. Mishnah Berurah 306:34; 500:8.
75. See Shemiras Shabbos Kehilchasah (14:42); see Shulchan Shlomo 306:16-2 for an elaboration.
76. It is even questionable whether or not it is permitted to measure the size of a room by counting tiles; Rav S.Z. Auerbach in Shemiras Shabbos Kehilchasah 29, note 94.
77. A scale, however, may not be used for this purpose. Shemiras Shabbos Kehilchasah 11:31.
78. Mishnah Berurah 504:21-22.
79. Mishnah Berurah 506:1.
80. Rema, O.C. 323:1 and Mishnah Berurah 5.
81. Mishnah Berurah 306:34.
82. Rav S.Z. Auerbach (Shemiras Shabbos Kehilchasah 29:40).
83. Mishnah Berurah 306:36. A healthy person, though, who is on a weight-control diet, may not measure precise portions.
84. Kaf Hachayim 618:40, see also Shemiras Shabbos Kehilchasah (29, footnote 57).