diff --git a/gql.go b/gql.go
index b9ca2c8..369833a 100644
--- a/gql.go
+++ b/gql.go
@@ -19,77 +19,77 @@ import (
 )
 
 func GraphiQLHandler() func(http.ResponseWriter, *http.Request) {
-  graphiql_string := `
-<!--
- *  Copyright (c) 2021 GraphQL Contributors
- *  All rights reserved.
- *
- *  This source code is licensed under the license found in the
- *  LICENSE file in the root directory of this source tree.
--->
-<!DOCTYPE html>
-<html lang="en">
-  <head>
-    <title>GraphiQL</title>
-    <style>
-      body {
-        height: 100%;
-        margin: 0;
-        width: 100%;
-        overflow: hidden;
-      }
-
-      #graphiql {
-        height: 100vh;
-      }
-    </style>
-
+  return func(w http.ResponseWriter, r * http.Request) {
+    graphiql_string := fmt.Sprintf(`
     <!--
-      This GraphiQL example depends on Promise and fetch, which are available in
-      modern browsers, but can be "polyfilled" for older browsers.
-      GraphiQL itself depends on React DOM.
-      If you do not want to rely on a CDN, you can host these files locally or
-      include them directly in your favored resource bundler.
+    *  Copyright (c) 2021 GraphQL Contributors
+    *  All rights reserved.
+    *
+    *  This source code is licensed under the license found in the
+    *  LICENSE file in the root directory of this source tree.
     -->
-    <script
-      crossorigin
-      src="https://unpkg.com/react@18/umd/react.development.js"
-    ></script>
-    <script
-      crossorigin
-      src="https://unpkg.com/react-dom@18/umd/react-dom.development.js"
-    ></script>
-
-    <!--
-      These two files can be found in the npm module, however you may wish to
-      copy them directly into your environment, or perhaps include them in your
-      favored resource bundler.
-     -->
-    <link rel="stylesheet" href="https://unpkg.com/graphiql/graphiql.min.css" />
-  </head>
-
-  <body>
-    <div id="graphiql">Loading...</div>
-    <script
-      src="https://unpkg.com/graphiql/graphiql.min.js"
-      type="application/javascript"
-    ></script>
-    <script>
-      const root = ReactDOM.createRoot(document.getElementById('graphiql'));
-      root.render(
-        React.createElement(GraphiQL, {
-          fetcher: GraphiQL.createFetcher({
-            url: 'http://localhost:8080/gql',
+    <!DOCTYPE html>
+    <html lang="en">
+    <head>
+      <title>GraphiQL</title>
+      <style>
+        body {
+          height: 100%%;
+          margin: 0;
+          width: 100%%;
+          overflow: hidden;
+        }
+    
+        #graphiql {
+          height: 100vh;
+        }
+      </style>
+    
+      <!--
+        This GraphiQL example depends on Promise and fetch, which are available in
+        modern browsers, but can be "polyfilled" for older browsers.
+        GraphiQL itself depends on React DOM.
+        If you do not want to rely on a CDN, you can host these files locally or
+        include them directly in your favored resource bundler.
+      -->
+      <script
+        crossorigin
+        src="https://unpkg.com/react@18/umd/react.development.js"
+      ></script>
+      <script
+        crossorigin
+        src="https://unpkg.com/react-dom@18/umd/react-dom.development.js"
+      ></script>
+    
+      <!--
+        These two files can be found in the npm module, however you may wish to
+        copy them directly into your environment, or perhaps include them in your
+        favored resource bundler.
+       -->
+      <link rel="stylesheet" href="https://unpkg.com/graphiql/graphiql.min.css" />
+    </head>
+    
+    <body>
+      <div id="graphiql">Loading...</div>
+      <script
+        src="https://unpkg.com/graphiql/graphiql.min.js"
+        type="application/javascript"
+      ></script>
+      <script>
+        const root = ReactDOM.createRoot(document.getElementById('graphiql'));
+        root.render(
+          React.createElement(GraphiQL, {
+    	fetcher: GraphiQL.createFetcher({
+	url: '%s/gql',
+    	}),
+    	defaultEditorToolsVisibility: true,
           }),
-          defaultEditorToolsVisibility: true,
-        }),
-      );
-    </script>
-  </body>
-</html>
-`
+        );
+      </script>
+    </body>
+    </html>
+    `, r.RequestURI)
 
-  return func(w http.ResponseWriter, r * http.Request) {
     w.Header().Set("Content-Type", "text/html; charset=utf-8")
     w.WriteHeader(http.StatusOK)
     io.WriteString(w, graphiql_string)
