diff --git a/src/ua_types.c b/src/ua_types.c
index 62441bbc116..04104143a44 100644
--- a/src/ua_types.c
+++ b/src/ua_types.c
@@ -63,14 +63,21 @@ guidOrder(const UA_Guid *p1, const UA_Guid *p2, const UA_DataType *_);
 const UA_DataType *
 UA_findDataTypeWithCustom(const UA_NodeId *typeId,
                           const UA_DataTypeArray *customTypes) {
-    /* Always look in built-in types first (may contain data types from all
-     * namespaces).
-     *
-     * TODO: The standard-defined types are ordered. See if binary search is
-     * more efficient. */
-    for(size_t i = 0; i < UA_TYPES_COUNT; ++i) {
-        if(nodeIdOrder(&UA_TYPES[i].typeId, typeId, NULL) == UA_ORDER_EQ)
-            return &UA_TYPES[i];
+    /* Always look in UA_TYPES first. UA_TYPES is ordered and contains only
+     * types from ns0 with a numeric identifier. So we can use binary search to
+     * speed this up. */
+    if(typeId->namespaceIndex == 0 && typeId->identifierType == UA_NODEIDTYPE_NUMERIC) {
+        size_t first = 0;
+        size_t last = UA_TYPES_COUNT - 1;
+        while(first <= last) {
+            size_t middle = (first+last) >> 1;
+            if(UA_TYPES[middle].typeId.identifier.numeric == typeId->identifier.numeric)
+                return &UA_TYPES[middle];
+            if(UA_TYPES[middle].typeId.identifier.numeric < typeId->identifier.numeric)
+                first = middle + 1;
+            else
+                last = middle - 1;
+        }
     }
 
     /* Search in the customTypes */
diff --git a/tests/check_types_builtin.c b/tests/check_types_builtin.c
index 7570de39df1..ff942b6957e 100644
--- a/tests/check_types_builtin.c
+++ b/tests/check_types_builtin.c
@@ -10,6 +10,7 @@
 #include "ua_util_internal.h"
 
 #include <stdlib.h>
+#include <stdio.h>
 #include <check.h>
 #include <float.h>
 #include <math.h>
@@ -1711,6 +1712,22 @@ START_TEST(UA_StatusCode_utils) {
 
 } END_TEST
 
+START_TEST(UA_type_lookup_speed) {
+    clock_t begin, finish;
+    begin = clock();
+
+    UA_NodeId readRequestId = UA_TYPES[UA_TYPES_READREQUEST].typeId;
+
+    for(size_t i = 0; i < 1000; i++) {
+        const UA_DataType *t = UA_findDataType(&readRequestId);
+        ck_assert(t == &UA_TYPES[UA_TYPES_READREQUEST]);
+    }
+
+    finish = clock();
+    double time_spent = (double)(finish - begin) / CLOCKS_PER_SEC;
+    printf("duration of the type lookup was %f s\n", time_spent);
+} END_TEST
+
 static Suite *testSuite_builtin(void) {
     Suite *s = suite_create("Built-in Data Types 62541-6 Table 1");
 
@@ -1803,6 +1820,10 @@ static Suite *testSuite_builtin(void) {
     tcase_add_test(tc_utils, UA_StatusCode_utils);
     suite_add_tcase(s, tc_utils);
 
+    TCase *tc_speed = tcase_create("speed");
+    tcase_add_test(tc_speed, UA_type_lookup_speed);
+    suite_add_tcase(s, tc_speed);
+
     return s;
 }