diff --git a/src/profile/ProfileModal.jsx b/src/profile/ProfileModal.tsx
similarity index 83%
rename from src/profile/ProfileModal.jsx
rename to src/profile/ProfileModal.tsx
index b0dee0e..26b99e9 100644
--- a/src/profile/ProfileModal.jsx
+++ b/src/profile/ProfileModal.tsx
@@ -15,6 +15,8 @@ limitations under the License.
 */
 
 import React, { useCallback, useEffect, useState } from "react";
+import { MatrixClient } from "matrix-js-sdk";
+
 import { Button } from "../button";
 import { useProfile } from "./useProfile";
 import { FieldRow, InputField, ErrorMessage } from "../input/Input";
@@ -22,7 +24,12 @@ import { Modal, ModalContent } from "../Modal";
 import { AvatarInputField } from "../input/AvatarInputField";
 import styles from "./ProfileModal.module.css";
 
-export function ProfileModal({ client, ...rest }) {
+interface Props {
+  client: MatrixClient;
+  onClose: () => {};
+  [rest: string]: unknown;
+}
+export function ProfileModal({ client, ...rest }: Props) {
   const { onClose } = rest;
   const {
     success,
@@ -50,13 +57,20 @@ export function ProfileModal({ client, ...rest }) {
     (e) => {
       e.preventDefault();
       const data = new FormData(e.target);
-      const displayName = data.get("displayName");
-      const avatar = data.get("avatar");
+      const displayNameDataEntry = data.get("displayName");
+      const avatar: File | string = data.get("avatar");
+
+      const avatarSize =
+        typeof avatar == "string" ? avatar.length : avatar.size;
+      const displayName =
+        typeof displayNameDataEntry == "string"
+          ? displayNameDataEntry
+          : displayNameDataEntry.name;
 
       saveProfile({
         displayName,
-        avatar: avatar && avatar.size > 0 ? avatar : undefined,
-        removeAvatar: removeAvatar && (!avatar || avatar.size === 0),
+        avatar: avatar && avatarSize > 0 ? avatar : undefined,
+        removeAvatar: removeAvatar && (!avatar || avatarSize === 0),
       });
     },
     [saveProfile, removeAvatar]
diff --git a/src/profile/useProfile.js b/src/profile/useProfile.ts
similarity index 66%
rename from src/profile/useProfile.js
rename to src/profile/useProfile.ts
index 2207dde..4eadcd8 100644
--- a/src/profile/useProfile.js
+++ b/src/profile/useProfile.ts
@@ -14,11 +14,36 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+import {
+  FileType,
+  MatrixClient,
+  MatrixEvent,
+  User,
+  UserEvent,
+} from "matrix-js-sdk";
 import { useState, useCallback, useEffect } from "react";
 
-export function useProfile(client) {
+interface ProfileLoadState {
+  success?: boolean;
+  loading?: boolean;
+  displayName: string;
+  avatarUrl: string;
+  error?: Error;
+}
+
+type ProfileSaveCallback = ({
+  displayName,
+  avatar,
+  removeAvatar,
+}: {
+  displayName: string;
+  avatar: FileType;
+  removeAvatar: boolean;
+}) => Promise<void>;
+
+export function useProfile(client: MatrixClient) {
   const [{ loading, displayName, avatarUrl, error, success }, setState] =
-    useState(() => {
+    useState<ProfileLoadState>(() => {
       const user = client?.getUser(client.getUserId());
 
       return {
@@ -31,7 +56,10 @@ export function useProfile(client) {
     });
 
   useEffect(() => {
-    const onChangeUser = (_event, { displayName, avatarUrl }) => {
+    const onChangeUser = (
+      _event: MatrixEvent,
+      { displayName, avatarUrl }: User
+    ) => {
       setState({
         success: false,
         loading: false,
@@ -41,24 +69,24 @@ export function useProfile(client) {
       });
     };
 
-    let user;
+    let user: User;
 
     if (client) {
       const userId = client.getUserId();
       user = client.getUser(userId);
-      user.on("User.displayName", onChangeUser);
-      user.on("User.avatarUrl", onChangeUser);
+      user.on(UserEvent.DisplayName, onChangeUser);
+      user.on(UserEvent.AvatarUrl, onChangeUser);
     }
 
     return () => {
       if (user) {
-        user.removeListener("User.displayName", onChangeUser);
-        user.removeListener("User.avatarUrl", onChangeUser);
+        user.removeListener(UserEvent.DisplayName, onChangeUser);
+        user.removeListener(UserEvent.AvatarUrl, onChangeUser);
       }
     };
   }, [client]);
 
-  const saveProfile = useCallback(
+  const saveProfile = useCallback<ProfileSaveCallback>(
     async ({ displayName, avatar, removeAvatar }) => {
       if (client) {
         setState((prev) => ({
@@ -71,7 +99,7 @@ export function useProfile(client) {
         try {
           await client.setDisplayName(displayName);
 
-          let mxcAvatarUrl;
+          let mxcAvatarUrl: string;
 
           if (removeAvatar) {
             await client.setAvatarUrl("");
@@ -87,11 +115,11 @@ export function useProfile(client) {
             loading: false,
             success: true,
           }));
-        } catch (error) {
+        } catch (error: unknown) {
           setState((prev) => ({
             ...prev,
             loading: false,
-            error,
+            error: error instanceof Error ? error : Error(error as string),
             success: false,
           }));
         }
@@ -102,5 +130,12 @@ export function useProfile(client) {
     [client]
   );
 
-  return { loading, error, displayName, avatarUrl, saveProfile, success };
+  return {
+    loading,
+    error,
+    displayName,
+    avatarUrl,
+    saveProfile,
+    success,
+  };
 }