diff --git a/keycloak_collective_portal/routes/register.py b/keycloak_collective_portal/routes/register.py
index 2c4368c..392bdb3 100644
--- a/keycloak_collective_portal/routes/register.py
+++ b/keycloak_collective_portal/routes/register.py
@@ -5,6 +5,7 @@ from datetime import datetime as dt
 from datetime import timedelta
 
 from fastapi import APIRouter, Depends, Form, Request
+from pydantic import EmailStr, errors
 
 from keycloak_collective_portal.dependencies import fresh_token, get_invites
 
@@ -61,17 +62,25 @@ def form_keycloak_register(
     password_again: str = Form(...),
     invited_by: str = Form(...),
 ):
+    context = {
+        "request": request,
+        "invited_by": invited_by,
+        "first_name": first_name,
+        "last_name": last_name,
+        "username": username,
+        "email": email,
+    }
+
+    try:
+        EmailStr().validate(email)
+    except errors.EmailError:
+        context["exception"] = "email is not valid?"
+        return request.app.state.templates.TemplateResponse(
+            "register.html", context=context
+        )
 
     if password != password_again:
-        context = {
-            "request": request,
-            "exception": "passwords don't match?",
-            "invited_by": invited_by,
-            "first_name": first_name,
-            "last_name": last_name,
-            "username": username,
-            "email": email,
-        }
+        context["exception"] = ("passwords don't match?",)
         return request.app.state.templates.TemplateResponse(
             "register.html", context=context
         )
diff --git a/poetry.lock b/poetry.lock
index e1fd73b..e140b85 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -163,6 +163,21 @@ sdist = ["setuptools-rust (>=0.11.4)"]
 ssh = ["bcrypt (>=3.1.5)"]
 test = ["pytest (>=6.0)", "pytest-cov", "pytest-subtests", "pytest-xdist", "pretend", "iso8601", "pytz", "hypothesis (>=1.11.4,!=3.79.2)"]
 
+[[package]]
+name = "dnspython"
+version = "2.1.0"
+description = "DNS toolkit"
+category = "main"
+optional = false
+python-versions = ">=3.6"
+
+[package.extras]
+dnssec = ["cryptography (>=2.6)"]
+doh = ["requests", "requests-toolbelt"]
+idna = ["idna (>=2.1)"]
+curio = ["curio (>=1.2)", "sniffio (>=1.1)"]
+trio = ["trio (>=0.14.0)", "sniffio (>=1.1)"]
+
 [[package]]
 name = "ecdsa"
 version = "0.17.0"
@@ -178,6 +193,18 @@ six = ">=1.9.0"
 gmpy = ["gmpy"]
 gmpy2 = ["gmpy2"]
 
+[[package]]
+name = "email-validator"
+version = "1.1.3"
+description = "A robust email syntax and deliverability validation library for Python 2.x/3.x."
+category = "main"
+optional = false
+python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,!=3.4.*,>=2.7"
+
+[package.dependencies]
+dnspython = ">=1.15.0"
+idna = ">=2.0.0"
+
 [[package]]
 name = "fastapi"
 version = "0.65.2"
@@ -642,7 +669,7 @@ python-versions = ">=3.6.1"
 [metadata]
 lock-version = "1.1"
 python-versions = "^3.9"
-content-hash = "d8f978355587c9f76a7888c64b7d1409de886670a4b6a51cdfc0eedbd6ba3009"
+content-hash = "ecf2a823da9679d30575e15c6fcb2eac6f1d9c323870831ba8c2f1fdc47e4fd1"
 
 [metadata.files]
 aiofiles = [
@@ -758,10 +785,18 @@ cryptography = [
     {file = "cryptography-3.4.7-pp37-pypy37_pp73-manylinux2014_x86_64.whl", hash = "sha256:ee77aa129f481be46f8d92a1a7db57269a2f23052d5f2433b4621bb457081cc9"},
     {file = "cryptography-3.4.7.tar.gz", hash = "sha256:3d10de8116d25649631977cb37da6cbdd2d6fa0e0281d014a5b7d337255ca713"},
 ]
+dnspython = [
+    {file = "dnspython-2.1.0-py3-none-any.whl", hash = "sha256:95d12f6ef0317118d2a1a6fc49aac65ffec7eb8087474158f42f26a639135216"},
+    {file = "dnspython-2.1.0.zip", hash = "sha256:e4a87f0b573201a0f3727fa18a516b055fd1107e0e5477cded4a2de497df1dd4"},
+]
 ecdsa = [
     {file = "ecdsa-0.17.0-py2.py3-none-any.whl", hash = "sha256:5cf31d5b33743abe0dfc28999036c849a69d548f994b535e527ee3cb7f3ef676"},
     {file = "ecdsa-0.17.0.tar.gz", hash = "sha256:b9f500bb439e4153d0330610f5d26baaf18d17b8ced1bc54410d189385ea68aa"},
 ]
+email-validator = [
+    {file = "email_validator-1.1.3-py2.py3-none-any.whl", hash = "sha256:5675c8ceb7106a37e40e2698a57c056756bf3f272cfa8682a4f87ebd95d8440b"},
+    {file = "email_validator-1.1.3.tar.gz", hash = "sha256:aa237a65f6f4da067119b7df3f13e89c25c051327b2b5b66dc075f33d62480d7"},
+]
 fastapi = [
     {file = "fastapi-0.65.2-py3-none-any.whl", hash = "sha256:39569a18914075b2f1aaa03bcb9dc96a38e0e5dabaf3972e088c9077dfffa379"},
     {file = "fastapi-0.65.2.tar.gz", hash = "sha256:8359e55d8412a5571c0736013d90af235d6949ec4ce978e9b63500c8f4b6f714"},
diff --git a/pyproject.toml b/pyproject.toml
index bc0dde5..220ede5 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -18,6 +18,7 @@ humanize = "^3.7.1"
 python-multipart = "^0.0.5"
 python-keycloak = "^0.25.0"
 aiofiles = "^0.7.0"
+email-validator = "^1.1.3"
 
 [tool.poetry.dev-dependencies]
 black = "^21.6b0"