diff --git a/library/x509_csr.c b/library/x509_csr.c
index d8ed04a..18ace67 100644
--- a/library/x509_csr.c
+++ b/library/x509_csr.c
@@ -418,7 +418,7 @@
     }
 
     ret = mbedtls_snprintf( p, n, "\n%s%-" BC "s: %d bits\n", prefix, key_size_str,
-                          (int) mbedtls_pk_get_size( &csr->pk ) );
+                          (int) mbedtls_pk_get_bitlen( &csr->pk ) );
     SAFE_SNPRINTF();
 
     return( (int) ( size - n ) );