diff --git a/include/crypto.h b/include/crypto.h
index 8619631..737dcb1 100644
--- a/include/crypto.h
+++ b/include/crypto.h
@@ -30,6 +30,7 @@ extern "C" {
 #define WHY2_SUM_BASE_PRIME 31 //PRIME FOR SUM BASE
 #define WHY2_SUM_MOD_PRIME 4294967295UL //PRIME FOR SUM MODULUS; 2^32 - 1
 
+#define WHY2_RECOMMENDED_PADDING_RATE(input_len) ((unsigned long) input_len / 3)
 #define WHY2_PADDING_NONZERO_TRIES 1024 //HOW MANY RANDOM NUMBERS TO TRY TO GENERATE WHEN PREVENTING 0s
 
 //FUNCTIONS