Is 5'6" Exactly 167 or 168 Cm? the Math Behind Rounding Height Measurements

Is is 5'6" Exactly 167 or 168 Cm? the Math Behind Rounding Height Measurements worth your attention? Uncover the pros and cons below.

Q1: If an online form requires a whole number, should I enter 167 or 168 cm?
Enter 168 cm. Because the true conversion of 66 inches is 167.64 cm, standard mathematical rounding protocol requires rounding up to 168. Entering 167 introduces a larger error margin (0.64 cm off) than entering 168 (0.36 cm off).

Q2: Why do some older conversion charts claim 5'6" is 167 cm?
Older printed conversion charts frequently relied on truncated internal calculations or rounded intermediate values (such as calculating 5 feet as 152 cm and 6 inches as 15 cm, then summing them to 167 cm). Modern direct calculation using the exact factor of 2.54 per inch resolves this to 167.64 cm.

Q3: Will having 167 cm on my passport cause issues if another ID says 168 cm?
No. International border protection agencies, including the TSA, Frontex, and Interpol, recognize that minor discrepancies of 1 to 2 centimeters are normal artifacts of imperial-to-metric administrative conversions and natural daily human spinal compression.