diff --git a/CHANGES b/CHANGES
index 69592ab..f3f554a 100644
--- a/CHANGES
+++ b/CHANGES
@@ -16,6 +16,7 @@
   fix typo breaking buffer_GETC in buffer (Marcus Winkler)
   fix typo breaking fmt_long for dest==NULL
   add fmt_*longlong()
+  add range check to scan_ulong, scan_ulonglong
 
 0.14:
   avoid bus errors in byte_copy
diff --git a/scan.h b/scan.h
index 41a62f2..60cd562 100644
--- a/scan.h
+++ b/scan.h
@@ -27,6 +27,11 @@ extern unsigned int scan_8long(const char *src,unsigned long *dest);
  * and return the number of bytes that were parsed */
 extern unsigned int scan_long(const char *src,signed long *dest);
 
+extern unsigned int scan_longlong(const char *src,signed long long *dest);
+extern unsigned int scan_ulonglong(const char *src,unsigned long long *dest);
+extern unsigned int scan_xlonglong(const char *src,unsigned long long *dest);
+extern unsigned int scan_8longlong(const char *src,unsigned long long *dest);
+
 extern unsigned int scan_uint(const char *src,unsigned int *dest);
 extern unsigned int scan_xint(const char *src,unsigned int *dest);
 extern unsigned int scan_8int(const char *src,unsigned int *dest);
diff --git a/scan/scan_long.c b/scan/scan_long.c
index 497c919..53aef1c 100644
--- a/scan/scan_long.c
+++ b/scan/scan_long.c
@@ -2,7 +2,7 @@
 
 unsigned int scan_long(const char *src,long *dest) {
   register const char *tmp;
-  register int l;
+  register long int l;
   register unsigned char c;
   int neg;
   tmp=src; l=0; neg=0;
diff --git a/scan/scan_ulong.c b/scan/scan_ulong.c
index 02d3f2b..385f98e 100644
--- a/scan/scan_ulong.c
+++ b/scan/scan_ulong.c
@@ -1,11 +1,13 @@
 #include "scan.h"
 
-unsigned int scan_ulong(const char *src,unsigned long *dest) {
+unsigned int scan_ulong(const char* src,unsigned long int* dest) {
   register const char *tmp=src;
-  register int l=0;
+  register unsigned long int l=0;
   register unsigned char c;
   while ((c=*tmp-'0')<10) {
+    unsigned long int m=l;
     l=l*10+c;
+    if ((l>>3) < m) break;
     ++tmp;
   }
   *dest=l;
diff --git a/test/fmt_longlong.c b/test/fmt_longlong.c
index 7a4014e..357d3dd 100644
--- a/test/fmt_longlong.c
+++ b/test/fmt_longlong.c
@@ -4,18 +4,24 @@
 
 main() {
   char buf[1024];
+  long long l;
 
   assert(fmt_longlong(0,12345)==5);
   assert(fmt_longlong(0,-12345)==6);
   assert(fmt_longlong(buf,12345)==5); buf[5]=0;
   assert(str_equal(buf,"12345"));
+  assert(scan_longlong(buf,&l)==5); assert(l==12345);
   assert(fmt_longlong(buf,-12345)==6); buf[6]=0;
   assert(str_equal(buf,"-12345"));
+  assert(scan_longlong(buf,&l)==6); assert(l==-12345);
 
   assert(fmt_longlong(0,1234567890)==10);
   assert(fmt_longlong(0,-1234567890)==11);
   assert(fmt_longlong(buf,1234567890)==10); buf[10]=0;
   assert(str_equal(buf,"1234567890"));
+  assert(scan_longlong(buf,&l)==10); assert(l==1234567890);
+
   assert(fmt_longlong(buf,-1234567890)==11); buf[11]=0;
   assert(str_equal(buf,"-1234567890"));
+  assert(scan_longlong(buf,&l)==11); assert(l==-1234567890);
 }