diff --git a/src/HTMLRenderer/general.cc b/src/HTMLRenderer/general.cc
index cda2d5d..68038c3 100644
--- a/src/HTMLRenderer/general.cc
+++ b/src/HTMLRenderer/general.cc
@@ -101,7 +101,8 @@ void HTMLRenderer::process(PDFDoc *doc)
 
         if(param->split_pages)
         {
-            auto page_fn = str_fmt("%s/%s%d.page", param->dest_dir.c_str(), param->output_filename.c_str(), i);
+            auto page_template_fn = str_fmt("%s/%s", param->dest_dir.c_str(), param->output_filename.c_str());
+            auto page_fn = str_fmt(page_template_fn, i);
             f_pages.fs.open((char*)page_fn, ofstream::binary); 
             if(!f_pages.fs)
                 throw string("Cannot open ") + (char*)page_fn + " for writing";
diff --git a/src/pdf2htmlEX.cc b/src/pdf2htmlEX.cc
index 806e91c..a54d5bf 100644
--- a/src/pdf2htmlEX.cc
+++ b/src/pdf2htmlEX.cc
@@ -10,6 +10,7 @@
 #include <string>
 #include <limits>
 #include <iostream>
+#include <regex>
 #include <getopt.h>
 
 #include <poppler-config.h>
@@ -213,7 +214,7 @@ int main(int argc, char **argv)
             if(get_suffix(param.input_filename) == ".pdf")
             {
                 if(param.split_pages)
-                    param.output_filename = s.substr(0, s.size() - 4);
+                    param.output_filename = s.substr(0, s.size() - 4) + "%d.page";
                 else
                     param.output_filename = s.substr(0, s.size() - 4) + ".html";
 
@@ -221,11 +222,16 @@ int main(int argc, char **argv)
             else
             {
                 if(param.split_pages)
-                    param.output_filename = s;
+                    param.output_filename = s + "%d.page";
                 else
                     param.output_filename = s + ".html";
                 
             }
+        }
+		else if(param.split_pages && !std::regex_match(param.output_filename, std::regex("^.*%[0-9]*d.*$")))
+        {
+            const string suffix = get_suffix(param.output_filename);
+            param.output_filename = param.output_filename.substr(0, param.output_filename.size() - suffix.size()) + "%d" + suffix;
         }
         if(param.css_filename.empty())
         {