Let $G=(V,T,S,P)$ be any context-free grammar without any $\lambda$-productions or unit productions. Let $K$ be the maximum number of symbols on the right of any production in $P$. The maximum number of production rules for any equivalent grammar in Chomsky normal form is given by:

Where $|\ |$ denotes the cardinality of the set.

In Chomsky Normal Form, every production must be of the form:

$A\rightarrow BC$

or

$A\rightarrow a$

If a production has maximum $K$ symbols on the right side, then to convert it into binary productions, at most $K-1$ productions are needed.

So, for $|P|$ productions, maximum productions required are:

$(K-1)|P|$

Also, for terminals, we may need separate productions for each terminal.

Number of terminals $=|T|$

So, total maximum number of productions:

$(K-1)|P|+|T|$