diff --git a/arch/sandbox/Kconfig b/arch/sandbox/Kconfig
index 5f55c7f28e..852a7c8bf2 100644
--- a/arch/sandbox/Kconfig
+++ b/arch/sandbox/Kconfig
@@ -17,11 +17,11 @@ config SANDBOX64
 
 config SANDBOX_RAM_SIZE_MB
 	int "RAM size in MiB"
-	default 128
+	default 256
 	range 64 4095 if !SANDBOX64
 	range 64 268435456 if SANDBOX64
 	help
-	  Memory size of the sandbox in MiB. The default value is 128 MiB.
+	  Memory size of the sandbox in MiB. The default value is 256 MiB.
 	  The minimum value is 64 MiB. The maximum value is 4095 MiB for the
 	  32bit sandbox.