To solve the equation \((8^3)^n = 8^{12}\), we can start by simplifying the left side:
Using the property of exponents \((a^m)^n = a^{m \cdot n}\), we can rewrite the left side:
\[ (8^3)^n = 8^{3n} \]
So, we can rewrite the equation as:
\[ 8^{3n} = 8^{12} \]
Since the bases are the same, we can set the exponents equal to each other:
\[ 3n = 12 \]
Now, we can solve for \(n\) by dividing both sides by 3:
\[ n = \frac{12}{3} = 4 \]
Thus, the value of \(n\) is:
\[ \boxed{4} \]