diff --git a/wetter/templates/export.html b/wetter/templates/export.html
index dabdc7e..7dcbc1c 100644
--- a/wetter/templates/export.html
+++ b/wetter/templates/export.html
@@ -9,6 +9,11 @@
 
 {% block content %}
 <section>
+  {% if e == "empty" %}
+  <div class="alert alert-danger" role="alert">
+    Ein oder mehrere Eingabefelder sind leer oder haben das falsche Format.
+  </div>
+  {% endif %}
   <h2>
     Export
     <small class="text-muted">Zeitraum wählen</small>
@@ -18,23 +23,13 @@
       <div class="col-sm-6">
           <div class="form-group">
               <label for="datetimepicker-from">von</label>
-              <div class="input-group" id="datetimepicker-from">
-                  <input type="text" name="from" class="form-control" placeholder="yyyy-mm-dd">
-                  <div class="input-group-append">
-                      <div class="input-group-text"><i class="fa fa-calendar"></i></div>
-                  </div>
-              </div>
+              <input type="date" value="{{ fr }}" name="from" class="form-control" id="datetimepicker-from" required>
           </div>
       </div>
       <div class="col-sm-6">
           <div class="form-group">
               <label for="datetimepicker-to">bis</label>
-              <div class="input-group" id="datetimepicker-to">
-                  <input type="text" name="to" class="form-control" placeholder="yyyy-mm-dd">
-                  <div class="input-group-append">
-                      <div class="input-group-text"><i class="fa fa-calendar"></i></div>
-                  </div>
-              </div>
+              <input type="date" value="{{ to }}" name="to" class="form-control" id="datetimepicker-to" required>
           </div>
       </div>
   </div>
diff --git a/wetter/templates/target.html b/wetter/templates/target.html
index 1b09590..436f958 100644
--- a/wetter/templates/target.html
+++ b/wetter/templates/target.html
@@ -17,17 +17,13 @@
     <div class="col-sm-6">
         <div class="form-group">
             <label for="datetimepicker-from">von</label>
-            <div class="input-group" id="datetimepicker-from">
-                <input type="text" value="{{ fr }}" class="form-control" placeholder="yyyy-mm-dd" disabled>
-            </div>
+            <input type="date" value="{{ fr }}" class="form-control" id="datetimepicker-from" disabled>
         </div>
     </div>
       <div class="col-sm-6">
           <div class="form-group">
               <label for="datetimepicker-to">bis</label>
-              <div class="input-group" id="datetimepicker-to">
-                  <input type="text" value="{{ to }}" class="form-control" placeholder="yyyy-mm-dd" disabled>
-              </div>
+              <input type="date" value="{{ to }}" class="form-control" id="datetimepicker-to" disabled>
           </div>
       </div>
   </div>
diff --git a/wetter/utils.py b/wetter/utils.py
index e59ea25..5795a46 100644
--- a/wetter/utils.py
+++ b/wetter/utils.py
@@ -4,3 +4,9 @@ from datetime import datetime
 
 def fromisoformat(str):
     return datetime.strptime(str, '%Y-%m-%d').date()
+
+def toisoformat(str, alt=""):
+    try:
+        return fromisoformat(str).isoformat()
+    except:
+        return alt
diff --git a/wetter/views.py b/wetter/views.py
index a505609..bec66f0 100644
--- a/wetter/views.py
+++ b/wetter/views.py
@@ -2,9 +2,10 @@
 
 from wetter import app, excel
 from wetter.models import Stations, Climate
-from wetter.utils import fromisoformat
-from flask import request, make_response, render_template, jsonify
+from wetter.utils import fromisoformat, toisoformat
+from flask import request, make_response, render_template, redirect, jsonify
 from datetime import datetime
+from urllib.parse import urlencode
 
 @app.route('/')
 def index():
@@ -28,18 +29,36 @@ def station(dwd_id):
 
 @app.route('/station/<dwd_id>/export/')
 def export(dwd_id):
+    fr = toisoformat(request.args.get('from'))
+    to = toisoformat(request.args.get('to'))
+    e = request.args.get('e')
+
     station = Stations.query.filter_by(dwd_id=dwd_id).first_or_404()
 
-    return render_template('export.html', station=station)
+    return render_template('export.html', e=e, station=station, fr=fr, to=to)
 
 @app.route('/station/<dwd_id>/export/target/')
 def export_target(dwd_id):
-    fr = fromisoformat(request.args.get('from'))
-    to = fromisoformat(request.args.get('to'))
+    fr = toisoformat(request.args.get('from'))
+    to = toisoformat(request.args.get('to'))
 
-    station = Stations.query.filter_by(dwd_id=dwd_id).first_or_404()
+    if fr and to:
+        station = Stations.query.filter_by(dwd_id=dwd_id).first_or_404()
 
-    return render_template('target.html', station=station, fr=fr.isoformat(), to=to.isoformat())
+        return render_template('target.html', station=station, fr=fr, to=to)
+
+    else:
+        qs = {
+            "e": "empty",
+        }
+
+        if fr:
+            qs["from"] = fr
+
+        if to:
+            qs["to"] = to
+
+        return redirect('/station/' + dwd_id + '/export/?' + urlencode(qs), code=302)
 
 def export_target_ce(request, dwd_id):
     fr = fromisoformat(request.args.get('from'))