diff --git a/src/conversionOfNumbers/conversionOfNumbers.h b/src/conversionOfNumbers/conversionOfNumbers.h
index 2b5e90c..92e1d85 100644
--- a/src/conversionOfNumbers/conversionOfNumbers.h
+++ b/src/conversionOfNumbers/conversionOfNumbers.h
@@ -2,5 +2,6 @@
 #define CONVERSIONOFNUMBERS_H
 
 char* convertIntToBinaryStr(int input);
+int binaryStrLen(int input);
 
 #endif
\ No newline at end of file