diff --git a/grub-core/tests/strtoull_test.c b/grub-core/tests/strtoull_test.c
new file mode 100644
index 000000000..7da615ff3
--- /dev/null
+++ b/grub-core/tests/strtoull_test.c
@@ -0,0 +1,63 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2016 Free Software Foundation, Inc.
+ *
+ *  GRUB is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/test.h>
+#include <grub/dl.h>
+
+GRUB_MOD_LICENSE ("GPLv3+");
+
+static void
+strtoull_testcase (const char *input, int base, unsigned long long expected,
+		   int num_digits, grub_err_t error)
+{
+  char *output;
+  unsigned long long value;
+  grub_errno = 0;
+  value = grub_strtoull(input, &output, base);
+  grub_test_assert (grub_errno == error,
+		    "unexpected error. Expected %d, got %d. Input \"%s\"",
+		    error, grub_errno, input);
+  if (grub_errno)
+    {
+      grub_errno = 0;
+      return;
+    }
+  grub_test_assert (input + num_digits == output,
+		    "unexpected number of digits. Expected %d, got %d, input \"%s\"",
+		    num_digits, (int) (output - input), input);
+  grub_test_assert (value == expected,
+		    "unexpected return value. Expected %llu, got %llu, input \"\%s\"",
+		    expected, value, input);
+}
+
+static void
+strtoull_test (void)
+{
+  strtoull_testcase ("9", 0, 9, 1, GRUB_ERR_NONE);
+  strtoull_testcase ("0xaa", 0, 0xaa, 4, GRUB_ERR_NONE);
+  strtoull_testcase ("0xff", 0, 0xff, 4, GRUB_ERR_NONE);
+  strtoull_testcase ("0", 10, 0, 1, GRUB_ERR_NONE);
+  strtoull_testcase ("8", 8, 0, 0, GRUB_ERR_BAD_NUMBER);
+  strtoull_testcase ("38", 8, 3, 1, GRUB_ERR_NONE);
+  strtoull_testcase ("7", 8, 7, 1, GRUB_ERR_NONE);
+  strtoull_testcase ("1]", 16, 1, 1, GRUB_ERR_NONE);
+  strtoull_testcase ("18446744073709551616", 10, 0, 0, GRUB_ERR_OUT_OF_RANGE);
+}
+
+
+GRUB_FUNCTIONAL_TEST (strtoull_test, strtoull_test);