diff --git a/library/mps_common.h b/library/mps_common.h
index 668876c..a2aee43 100644
--- a/library/mps_common.h
+++ b/library/mps_common.h
@@ -169,7 +169,7 @@
  *
  */
 typedef size_t mbedtls_mps_stored_size_t;
-#define MBEDTLS_MPS_STORED_SIZE_MAX  ( (mbedtls_mps_stored_size_t) -1 )
+#define MBEDTLS_MPS_STORED_SIZE_MAX  (SIZE_MAX)
 
 /** \brief The type of buffer sizes and offsets used in the MPS API
  *         and implementation.
@@ -183,7 +183,7 @@
  *         so almost 10%.
  */
 typedef size_t mbedtls_mps_size_t;
-#define MBEDTLS_MPS_SIZE_MAX  ( (mbedtls_mps_size_t) -1 )
+#define MBEDTLS_MPS_SIZE_MAX  (SIZE_MAX)
 
 #if MBEDTLS_MPS_STORED_SIZE_MAX > MBEDTLS_MPS_SIZE_MAX
 #error "Misconfiguration of mbedtls_mps_size_t and mbedtls_mps_stored_size_t."