4 log 16The log base 2 calculator quickly computes the value of the logarithm Similarly, log₂ 16 = 4 or log₂ 32 = 5. But what is, say, log₂ 5? Surely, 5log2 16 = 4, since 24 = 2 × 2 × 2 × 2 = 16. · Logarithms can also be negative: log 2 1 2 = − 1 {textstyle log _{2}!{frac {1}{2}}=