Half of 33 3/8 inches is 16 11/16 inches (16.6875″, 423.86 mm).
How to Calculate It
Convert 33 3/8 to an improper fraction, divide by 2, then simplify. 33 3/8 = 267/8, divided by 2 = 267/16, simplified to 16 11/16.
On the Tape Measure
The mark at 16 11/16 inches (16.6875″) is a standard mark on all tapes.
To find half of any tape measure measurement, enter it in TapeMath and tap the Half It button. The result appears instantly on the visual tape.