diff --git a/src/components/LoginPage.js b/src/components/LoginPage.js
index 520a26c..984300b 100644
--- a/src/components/LoginPage.js
+++ b/src/components/LoginPage.js
@@ -1,5 +1,7 @@
 import React, { useState } from "react";
 import {
+  fetchUtils,
+  FormDataConsumer,
   Notification,
   useLogin,
   useNotify,
@@ -9,7 +11,7 @@ import {
   PasswordInput,
   TextInput,
 } from "react-admin";
-import { Form } from "react-final-form";
+import { Form, useForm } from "react-final-form";
 import {
   Avatar,
   Button,
@@ -36,7 +38,7 @@ const useStyles = makeStyles(theme => ({
     backgroundSize: "cover",
   },
   card: {
-    minWidth: 300,
+    minWidth: "30em",
     marginTop: "6em",
   },
   avatar: {
@@ -72,7 +74,7 @@ const LoginPage = ({ theme }) => {
   var locale = useLocale();
   const setLocale = useSetLocale();
   const translate = useTranslate();
-  const homeserver = localStorage.getItem("base_url");
+  const base_url = localStorage.getItem("base_url");
 
   const renderInput = ({
     meta: { touched, error } = {},
@@ -90,23 +92,21 @@ const LoginPage = ({ theme }) => {
 
   const validate = values => {
     const errors = {};
-    if (!values.homeserver) {
-      errors.homeserver = translate("ra.validation.required");
-    } else {
-      if (!values.homeserver.match(/^(http|https):\/\//)) {
-        errors.homeserver = translate("synapseadmin.auth.protocol_error");
-      } else if (
-        !values.homeserver.match(/^(http|https):\/\/[a-zA-Z0-9\-.]+$/)
-      ) {
-        errors.homeserver = translate("synapseadmin.auth.url_error");
-      }
-    }
     if (!values.username) {
       errors.username = translate("ra.validation.required");
     }
     if (!values.password) {
       errors.password = translate("ra.validation.required");
     }
+    if (!values.base_url) {
+      errors.base_url = translate("ra.validation.required");
+    } else {
+      if (!values.base_url.match(/^(http|https):\/\//)) {
+        errors.base_url = translate("synapseadmin.auth.protocol_error");
+      } else if (!values.base_url.match(/^(http|https):\/\/[a-zA-Z0-9\-.]+$/)) {
+        errors.base_url = translate("synapseadmin.auth.url_error");
+      }
+    }
     return errors;
   };
 
@@ -125,9 +125,75 @@ const LoginPage = ({ theme }) => {
     });
   };
 
+  const extractHomeServer = username => {
+    const usernameRegex = /@[a-zA-Z0-9._=\-/]+:([a-zA-Z0-9\-.]+\.[a-zA-Z]+)/;
+    if (!username) return null;
+    const res = username.match(usernameRegex);
+    if (res) return res[1];
+    return null;
+  };
+
+  const UserData = ({ formData }) => {
+    const form = useForm();
+
+    const handleUsernameChange = _ => {
+      if (formData.base_url) return;
+      // check if username is a full qualified userId then set base_url accordially
+      const home_server = extractHomeServer(formData.username);
+      const wellKnownUrl = `https://${home_server}/.well-known/matrix/client`;
+      if (home_server) {
+        // fetch .well-known entry to get base_url
+        fetchUtils
+          .fetchJson(wellKnownUrl, { method: "GET" })
+          .then(({ json }) => {
+            form.change("base_url", json["m.homeserver"].base_url);
+          })
+          .catch(_ => {
+            // if there is no .well-known entry, try the home server name
+            form.change("base_url", `https://${home_server}`);
+          });
+      }
+    };
+
+    return (
+      <div>
+        <div className={classes.input}>
+          <TextInput
+            autoFocus
+            name="username"
+            component={renderInput}
+            label={translate("ra.auth.username")}
+            disabled={loading}
+            onBlur={handleUsernameChange}
+            fullWidth
+          />
+        </div>
+        <div className={classes.input}>
+          <PasswordInput
+            name="password"
+            component={renderInput}
+            label={translate("ra.auth.password")}
+            type="password"
+            disabled={loading}
+            fullWidth
+          />
+        </div>
+        <div className={classes.input}>
+          <TextInput
+            name="base_url"
+            component={renderInput}
+            label={translate("synapseadmin.auth.base_url")}
+            disabled={loading}
+            fullWidth
+          />
+        </div>
+      </div>
+    );
+  };
+
   return (
     <Form
-      initialValues={{ homeserver: homeserver }}
+      initialValues={{ base_url: base_url }}
       onSubmit={handleSubmit}
       validate={validate}
       render={({ handleSubmit }) => (
@@ -156,35 +222,9 @@ const LoginPage = ({ theme }) => {
                     <MenuItem value="en">English</MenuItem>
                   </Select>
                 </div>
-                <div className={classes.input}>
-                  <TextInput
-                    name="homeserver"
-                    component={renderInput}
-                    label={translate("synapseadmin.auth.homeserver")}
-                    disabled={loading}
-                    fullWidth
-                  />
-                </div>
-                <div className={classes.input}>
-                  <TextInput
-                    autoFocus
-                    name="username"
-                    component={renderInput}
-                    label={translate("ra.auth.username")}
-                    disabled={loading}
-                    fullWidth
-                  />
-                </div>
-                <div className={classes.input}>
-                  <PasswordInput
-                    name="password"
-                    component={renderInput}
-                    label={translate("ra.auth.password")}
-                    type="password"
-                    disabled={loading}
-                    fullWidth
-                  />
-                </div>
+                <FormDataConsumer>
+                  {formDataProps => <UserData {...formDataProps} />}
+                </FormDataConsumer>
               </div>
               <CardActions className={classes.actions}>
                 <Button
diff --git a/src/i18n/de.js b/src/i18n/de.js
index 12db9bf..9871a89 100644
--- a/src/i18n/de.js
+++ b/src/i18n/de.js
@@ -4,8 +4,9 @@ export default {
   ...germanMessages,
   synapseadmin: {
     auth: {
-      homeserver: "Heimserver",
+      base_url: "Heimserver URL",
       welcome: "Willkommen bei Synapse-admin",
+      username_error: "Bitte vollständigen Nutzernamen angeben: '@user:domain'",
       protocol_error: "Die URL muss mit 'http://' oder 'https://' beginnen",
       url_error: "Keine gültige Matrix Server URL",
     },
diff --git a/src/i18n/en.js b/src/i18n/en.js
index 8a3974c..ff0864a 100644
--- a/src/i18n/en.js
+++ b/src/i18n/en.js
@@ -4,8 +4,9 @@ export default {
   ...englishMessages,
   synapseadmin: {
     auth: {
-      homeserver: "Homeserver",
+      base_url: "Homeserver URL",
       welcome: "Welcome to Synapse-admin",
+      username_error: "Please enter fully qualified user ID: '@user:domain'",
       protocol_error: "URL has to start with 'http://' or 'https://'",
       url_error: "Not a valid Matrix server URL",
     },