diff --git a/configure b/configure
index c17423f..e3b6368 100755
--- a/configure
+++ b/configure
@@ -17786,6 +17786,7 @@
 wine_fn_config_test dlls/twain_32/tests twain_32_test
 wine_fn_config_dll typelib.dll16 enable_win16
 wine_fn_config_dll ucrtbase enable_ucrtbase
+wine_fn_config_test dlls/ucrtbase/tests ucrtbase_test
 wine_fn_config_dll unicows enable_unicows implib
 wine_fn_config_dll updspapi enable_updspapi
 wine_fn_config_dll url enable_url implib
diff --git a/configure.ac b/configure.ac
index 7ab221b..114a7fa 100644
--- a/configure.ac
+++ b/configure.ac
@@ -3336,6 +3336,7 @@
 WINE_CONFIG_TEST(dlls/twain_32/tests)
 WINE_CONFIG_DLL(typelib.dll16,enable_win16)
 WINE_CONFIG_DLL(ucrtbase)
+WINE_CONFIG_TEST(dlls/ucrtbase/tests)
 WINE_CONFIG_DLL(unicows,,[implib])
 WINE_CONFIG_DLL(updspapi)
 WINE_CONFIG_DLL(url,,[implib])
diff --git a/dlls/msvcrt/string.c b/dlls/msvcrt/string.c
index 980d492..dde95ac 100644
--- a/dlls/msvcrt/string.c
+++ b/dlls/msvcrt/string.c
@@ -314,6 +314,7 @@
     double ret;
     long double lret=1, expcnt = 10;
     BOOL found_digit = FALSE, negexp;
+    int base = 10;
 
     if(err)
         *err = 0;
@@ -339,16 +340,50 @@
     } else  if(*p == '+')
         p++;
 
-    while(isdigit(*p)) {
+#if _MSVCR_VER >= 140
+    if(tolower(p[0]) == 'i' && tolower(p[1]) == 'n' && tolower(p[2]) == 'f') {
+        if(end)
+            *end = (char*) &p[3];
+        if(tolower(p[3]) == 'i' && tolower(p[4]) == 'n' && tolower(p[5]) == 'i' &&
+           tolower(p[6]) == 't' && tolower(p[7]) == 'y' && end)
+            *end = (char*) &p[8];
+        return sign*INFINITY;
+    }
+    if(tolower(p[0]) == 'n' &&
+       tolower(p[1]) == 'a' &&
+       tolower(p[2]) == 'n') {
+        if(end)
+            *end = (char*) &p[3];
+        return NAN;
+    }
+
+    if(p[0] == '0' && tolower(p[1]) == 'x') {
+        base = 16;
+        expcnt = 2;
+        p += 2;
+    }
+#endif
+
+    while(isdigit(*p) ||
+          (base == 16 && ((*p >= 'a' && *p <= 'f') || (*p >= 'A' && *p <= 'F')))) {
+        char c = *p++;
+        int val;
         found_digit = TRUE;
-        hlp = d*10+*(p++)-'0';
-        if(d>MSVCRT_UI64_MAX/10 || hlp<d) {
+        if (isdigit(c))
+            val = c - '0';
+        else if (c >= 'a' && c <= 'f')
+            val = 10 + c - 'a';
+        else
+            val = 10 + c - 'A';
+        hlp = d*base+val;
+        if(d>MSVCRT_UI64_MAX/base || hlp<d) {
             exp++;
             break;
         } else
             d = hlp;
     }
-    while(isdigit(*p)) {
+    while(isdigit(*p) ||
+          (base == 16 && ((*p >= 'a' && *p <= 'f') || (*p >= 'A' && *p <= 'F')))) {
         exp++;
         p++;
     }
@@ -356,16 +391,25 @@
     if(*p == *locinfo->lconv->decimal_point)
         p++;
 
-    while(isdigit(*p)) {
+    while(isdigit(*p) ||
+          (base == 16 && ((*p >= 'a' && *p <= 'f') || (*p >= 'A' && *p <= 'F')))) {
+        char c = *p++;
+        int val;
         found_digit = TRUE;
-        hlp = d*10+*(p++)-'0';
-        if(d>MSVCRT_UI64_MAX/10 || hlp<d)
+        if (isdigit(c))
+            val = c - '0';
+        else if (c >= 'a' && c <= 'f')
+            val = 10 + c - 'a';
+        else
+            val = 10 + c - 'A';
+        hlp = d*base+val;
+        if(d>MSVCRT_UI64_MAX/base || hlp<d)
             break;
-
         d = hlp;
         exp--;
     }
-    while(isdigit(*p))
+    while(isdigit(*p) ||
+          (base == 16 && ((*p >= 'a' && *p <= 'f') || (*p >= 'A' && *p <= 'F'))))
         p++;
 
     if(!found_digit) {
@@ -374,7 +418,11 @@
         return 0.0;
     }
 
-    if(*p=='e' || *p=='E' || *p=='d' || *p=='D') {
+    if(base == 16)
+        exp *= 4;
+
+    if((base == 10 && (*p=='e' || *p=='E' || *p=='d' || *p=='D')) ||
+       (base == 16 && (*p=='p' || *p=='P'))) {
         int e=0, s=1;
 
         p++;
diff --git a/dlls/ucrtbase/tests/Makefile.in b/dlls/ucrtbase/tests/Makefile.in
new file mode 100644
index 0000000..2a57e5e
--- /dev/null
+++ b/dlls/ucrtbase/tests/Makefile.in
@@ -0,0 +1,5 @@
+TESTDLL   = ucrtbase.dll
+APPMODE   = -mno-cygwin
+
+C_SRCS = \
+	string.c
diff --git a/dlls/ucrtbase/tests/string.c b/dlls/ucrtbase/tests/string.c
new file mode 100644
index 0000000..c251558
--- /dev/null
+++ b/dlls/ucrtbase/tests/string.c
@@ -0,0 +1,121 @@
+/*
+ * Copyright 2015 Martin Storsjo
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#include <errno.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <wchar.h>
+#include <stdio.h>
+
+#include <windef.h>
+#include <winbase.h>
+#include "wine/test.h"
+
+#include <math.h>
+
+#ifndef INFINITY
+static inline float __port_infinity(void)
+{
+    static const unsigned __inf_bytes = 0x7f800000;
+    return *(const float *)&__inf_bytes;
+}
+#define INFINITY __port_infinity()
+#endif
+
+#ifndef NAN
+static inline float __port_nan(void)
+{
+    static const unsigned __nan_bytes = 0x7fc00000;
+    return *(const float *)&__nan_bytes;
+}
+#define NAN __port_nan()
+#endif
+
+static double (CDECL *p_strtod)(const char*, char** end);
+
+static BOOL init(void)
+{
+    HMODULE module;
+
+    module = LoadLibraryA("ucrtbase.dll");
+    if (!module)
+    {
+        win_skip("ucrtbase.dll not installed\n");
+        return FALSE;
+    }
+
+    p_strtod = (void*)GetProcAddress(module, "strtod");
+    return TRUE;
+}
+
+static BOOL local_isnan(double d)
+{
+    return d != d;
+}
+
+#define test_strtod_str(string, value, length) _test_strtod_str(__LINE__, string, value, length)
+static void _test_strtod_str(int line, const char* string, double value, int length)
+{
+    char *end;
+    double d;
+    d = p_strtod(string, &end);
+    if (local_isnan(value))
+        ok_(__FILE__, line)(local_isnan(d), "d = %lf (\"%s\")\n", d, string);
+    else
+        ok_(__FILE__, line)(d == value, "d = %lf (\"%s\")\n", d, string);
+    ok_(__FILE__, line)(end == string + length, "incorrect end (%d, \"%s\")\n", (int)(end - string), string);
+}
+
+static void test_strtod(void)
+{
+    test_strtod_str("infinity", INFINITY, 8);
+    test_strtod_str("INFINITY", INFINITY, 8);
+    test_strtod_str("InFiNiTy", INFINITY, 8);
+    test_strtod_str("INF", INFINITY, 3);
+    test_strtod_str("-inf", -INFINITY, 4);
+    test_strtod_str("inf42", INFINITY, 3);
+    test_strtod_str("inffoo", INFINITY, 3);
+    test_strtod_str("infini", INFINITY, 3);
+
+    test_strtod_str("NAN", NAN, 3);
+    test_strtod_str("nan", NAN, 3);
+    test_strtod_str("NaN", NAN, 3);
+
+    test_strtod_str("0x42", 66, 4);
+    test_strtod_str("0X42", 66, 4);
+    test_strtod_str("-0x42", -66, 5);
+    test_strtod_str("0x1p1", 2, 5);
+    test_strtod_str("0x1P1", 2, 5);
+    test_strtod_str("0x1p+1", 2, 6);
+    test_strtod_str("0x2p-1", 1, 6);
+    test_strtod_str("0xA", 10, 3);
+    test_strtod_str("0xa", 10, 3);
+    test_strtod_str("0xABCDEF", 11259375, 8);
+    test_strtod_str("0Xabcdef", 11259375, 8);
+
+    test_strtod_str("0x1.1", 1.0625, 5);
+    test_strtod_str("0x1.1p1", 2.125, 7);
+    test_strtod_str("0x1.A", 1.625, 5);
+    test_strtod_str("0x1p1a", 2, 5);
+}
+
+START_TEST(string)
+{
+    if (!init()) return;
+    test_strtod();
+}