How to convert from hexadecimal to decimal?

Assume we have a n-digits hexadecimal number:

d_n-1 ... d₃ d₂ d₁ d₀

Convert each digit of the hexadecimal to the corresponding decimal number using this table for reference:

Multiply each digit of the hexadecimal number with its corresponding 16ⁿ, where n is the position of the digit.

decimal number = d₀×16⁰ + d₁×16¹ + d₂×16² + ...

Convert the fractional part from hexadecimal to decimal:

Multiply each digit of the fractional digit with its corresponding 16^-n, where n is the position of the digit.

0.d₀ d₁ d₂ ... d_n-1

fractional part = d₀×16^-1 + d₁×16^-2 + ... + d_n-1×16ⁿ

Example:

6D.3C₁₆ = (6 × 16¹) + (13 × 16⁰) + (3 × 8^-1) + (12 × 16^-2) = 109.234375₁₀

Below is the reference table for converting binary number to decimal, octal, hexadecimal, ranging from 0₁₀ to 15₁₀: