diff --git a/lib/Router/responseType.js b/lib/Router/responseType.js
index a456abc..4c57be7 100644
--- a/lib/Router/responseType.js
+++ b/lib/Router/responseType.js
@@ -1,5 +1,11 @@
 'use strict';
 
+var _mime = require('mime');
+
+var _mime2 = _interopRequireDefault(_mime);
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
 /**
  * Parse response type middleware
  *
@@ -11,7 +17,7 @@ module.exports = function responseType(req, res, next) {
 
   if (!req.headers) req.headers = {};
 
-  req.headers.accept = parseResponseType(req);
+  parseResponseType(req);
 
   next();
 };
@@ -25,8 +31,6 @@ module.exports = function responseType(req, res, next) {
  * @return {String}     the response type string
  */
 function parseResponseType(req) {
-  if (req.extension) return req.extension.toLowerCase();
-
   if (req.query && req.query.responseType) {
     if (req.query.responseType == 'modal') {
       // suport for old we.js contentOnly api
@@ -34,11 +38,10 @@ function parseResponseType(req) {
       req.query.contentOnly = true;
     }
 
-    return req.query.responseType.toLowerCase();
+    req.headers.accept = _mime2.default.lookup(req.query.responseType.toLowerCase());
   }
 
-  var type = req.accepts(req.we.config.responseTypes);
-  if (type) return type;
+  if (req.accepts(req.we.config.responseTypes)) return;
 
-  return req.we.config.defaultResponseType;
+  req.headers.accept = req.we.config.defaultResponseType;
 }
\ No newline at end of file
diff --git a/lib/index.js b/lib/index.js
index 9982caf..042e16a 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -394,12 +394,15 @@ We.prototype.startServer = function startExpressServer(cb) {
       // parse extension if not is public folder
       if (!we.router.isPublicFolder(req.url)) {
         req.extension = we.router.splitExtensionFromURL(req.url);
+
         if (req.extension) {
-          // check if is valid this extension and is one of acceptable extensions
-          if (we.config.responseTypes.indexOf(req.extension) > -1) {
+          var format = we.utils.mime.lookup(req.extension);
+
+          if (req.we.config.responseTypes.indexOf(format) !== -1) {
+            // update the header response format with extension format
+            req.headers.accept = format;
+            // update the old url
             req.url = req.url.replace('.' + req.extension, '');
-          } else {
-            req.extension = null;
           }
         }
       }
diff --git a/lib/utils/index.js b/lib/utils/index.js
index f483b7c..2154aca 100644
--- a/lib/utils/index.js
+++ b/lib/utils/index.js
@@ -16,6 +16,7 @@ module.exports = {
   mkdirp: require('mkdirp'),
   string: require('string'),
   cookieParser: require('cookie-parser'),
+  mime: require('mime'),
 
   /**
    * Is authenticated method usable if we-plugin-auth not is installed
diff --git a/plugin.js b/plugin.js
index df43e0c..7db25ad 100644
--- a/plugin.js
+++ b/plugin.js
@@ -23,6 +23,7 @@ module.exports = function loadPlugin(projectPath, Plugin) {
     queryDefaultLimit: 25,
     queryMaxLimit: 300,
     // map reponseType response types, used by Accept headers in response selection
+    // this is set automaticaly after add new response types
     responseTypes: [
       'application/json',
       'application/vnd.api+json'
diff --git a/src/Router/responseType.js b/src/Router/responseType.js
index 989da66..16018ad 100644
--- a/src/Router/responseType.js
+++ b/src/Router/responseType.js
@@ -1,3 +1,5 @@
+import mime from 'mime'
+
 /**
  * Parse response type middleware
  *
@@ -9,7 +11,7 @@ module.exports = function responseType (req, res, next){
 
   if (!req.headers) req.headers = {};
 
-  req.headers.accept = parseResponseType(req);
+  parseResponseType(req);
 
   next();
 }
@@ -23,8 +25,6 @@ module.exports = function responseType (req, res, next){
  * @return {String}     the response type string
  */
 function parseResponseType (req) {
-  if (req.extension) return req.extension.toLowerCase();
-
   if (req.query && req.query.responseType) {
     if (req.query.responseType == 'modal') {
       // suport for old we.js contentOnly api
@@ -32,11 +32,11 @@ function parseResponseType (req) {
       req.query.contentOnly = true;
     }
 
-    return req.query.responseType.toLowerCase();
+    req.headers.accept = mime.lookup(req.query.responseType.toLowerCase());
   }
 
-  var type = req.accepts(req.we.config.responseTypes);
-  if (type) return type;
+  if (req.accepts(req.we.config.responseTypes))
+    return;
 
-  return req.we.config.defaultResponseType;
+  req.headers.accept = req.we.config.defaultResponseType;
 }
\ No newline at end of file
diff --git a/src/index.js b/src/index.js
index 588939e..5db2703 100644
--- a/src/index.js
+++ b/src/index.js
@@ -374,12 +374,15 @@ We.prototype.startServer = function startExpressServer(cb) {
       // parse extension if not is public folder
       if (!we.router.isPublicFolder(req.url)) {
         req.extension = we.router.splitExtensionFromURL(req.url)
+
         if (req.extension) {
-          // check if is valid this extension and is one of acceptable extensions
-          if (we.config.responseTypes.indexOf(req.extension) >-1) {
+          let format = we.utils.mime.lookup(req.extension)
+
+          if (req.we.config.responseTypes.includes(format)) {
+            // update the header response format with extension format
+            req.headers.accept = format
+            // update the old url
             req.url = req.url.replace('.'+req.extension, '')
-          } else {
-            req.extension = null
           }
         }
       }
diff --git a/src/utils/index.js b/src/utils/index.js
index cf03476..43fcf3b 100644
--- a/src/utils/index.js
+++ b/src/utils/index.js
@@ -14,6 +14,7 @@ module.exports = {
   mkdirp: require('mkdirp'),
   string: require('string'),
   cookieParser: require('cookie-parser'),
+  mime: require('mime'),
 
   /**
    * Is authenticated method usable if we-plugin-auth not is installed