diff --git a/include/mbedtls/bignum.h b/include/mbedtls/bignum.h
index 87520726cc..71d7b97672 100644
--- a/include/mbedtls/bignum.h
+++ b/include/mbedtls/bignum.h
@@ -51,11 +51,11 @@
 
 #if !defined(MBEDTLS_MPI_WINDOW_SIZE)
 /*
- * Maximum window size used for modular exponentiation. Default: 2
+ * Maximum window size used for modular exponentiation. Default: 3
  * Minimum value: 1. Maximum value: 6.
  *
  * Result is an array of ( 2 ** MBEDTLS_MPI_WINDOW_SIZE ) MPIs used
- * for the sliding window calculation. (So 64 by default)
+ * for the sliding window calculation. (So 8 by default)
  *
  * Reduction in size, reduces speed.
  */