diff --git a/tools/test-js-with-node b/tools/test-js-with-node
index df7d71538e..68ef214e8c 100755
--- a/tools/test-js-with-node
+++ b/tools/test-js-with-node
@@ -142,7 +142,7 @@ EXEMPT_FILES = make_set(
         "web/src/read_receipts.js",
         "web/src/ready.ts",
         "web/src/realm_icon.ts",
-        "web/src/realm_logo.js",
+        "web/src/realm_logo.ts",
         "web/src/realm_playground.ts",
         "web/src/realm_user_settings_defaults.ts",
         "web/src/recent_view_ui.js",
diff --git a/web/src/page_params.ts b/web/src/page_params.ts
index 0d359a0ec1..b116bb992d 100644
--- a/web/src/page_params.ts
+++ b/web/src/page_params.ts
@@ -22,6 +22,7 @@ export const page_params: {
     is_spectator: boolean;
     max_avatar_file_size_mib: number;
     max_icon_file_size_mib: number;
+    max_logo_file_size_mib: number;
     muted_users: {id: number; timestamp: number}[];
     needs_tutorial: boolean;
     page_load_time: number;
@@ -41,6 +42,10 @@ export const page_params: {
     realm_invite_to_realm_policy: number;
     realm_invite_to_stream_policy: number;
     realm_is_zephyr_mirror_realm: boolean;
+    realm_logo_source: string;
+    realm_logo_url: string;
+    realm_night_logo_source: string;
+    realm_night_logo_url: string;
     realm_move_messages_between_streams_policy: number;
     realm_name_changes_disabled: boolean;
     realm_name: string;
diff --git a/web/src/realm_logo.js b/web/src/realm_logo.ts
similarity index 80%
rename from web/src/realm_logo.js
rename to web/src/realm_logo.ts
index b4ed1702f9..7515e37b2d 100644
--- a/web/src/realm_logo.js
+++ b/web/src/realm_logo.ts
@@ -5,8 +5,9 @@ import {page_params} from "./page_params";
 import * as settings_data from "./settings_data";
 import * as ui_util from "./ui_util";
 import * as upload_widget from "./upload_widget";
+import type {UploadFunction} from "./upload_widget";
 
-export function build_realm_logo_widget(upload_function, is_night) {
+export function build_realm_logo_widget(upload_function: UploadFunction, is_night: boolean): void {
     let logo_section_id = "#realm-day-logo-upload-widget";
     let logo_source = page_params.realm_logo_source;
 
@@ -16,11 +17,11 @@ export function build_realm_logo_widget(upload_function, is_night) {
     }
 
     const $delete_button_elem = $(logo_section_id + " .image-delete-button");
-    const $file_input_elem = $(logo_section_id + " .image_file_input");
+    const $file_input_elem = $<HTMLInputElement>(logo_section_id + " .image_file_input");
     const $file_input_error_elem = $(logo_section_id + " .image_file_input_error");
     const $upload_button_elem = $(logo_section_id + " .image_upload_button");
 
-    const get_file_input = function () {
+    const get_file_input = function (): JQuery<HTMLInputElement> {
         return $file_input_elem.expectOne();
     };
 
@@ -38,7 +39,7 @@ export function build_realm_logo_widget(upload_function, is_night) {
     $delete_button_elem.on("click", (e) => {
         e.preventDefault();
         e.stopPropagation();
-        channel.del({
+        void channel.del({
             url: "/json/realm/logo",
             data,
         });
@@ -53,7 +54,11 @@ export function build_realm_logo_widget(upload_function, is_night) {
     );
 }
 
-function change_logo_delete_button(logo_source, $logo_delete_button, $file_input) {
+function change_logo_delete_button(
+    logo_source: string,
+    $logo_delete_button: JQuery,
+    $file_input: JQuery<HTMLInputElement>,
+): void {
     if (logo_source === "U") {
         $logo_delete_button.show();
     } else {
@@ -64,9 +69,11 @@ function change_logo_delete_button(logo_source, $logo_delete_button, $file_input
     }
 }
 
-export function render() {
-    const $file_input = $("#realm-day-logo-upload-widget .image_file_input");
-    const $night_file_input = $("#realm-night-logo-upload-widget .realm-logo-file-input");
+export function render(): void {
+    const $file_input = $<HTMLInputElement>("#realm-day-logo-upload-widget .image_file_input");
+    const $night_file_input = $<HTMLInputElement>(
+        "#realm-night-logo-upload-widget .realm-logo-file-input",
+    );
     $("#realm-day-logo-upload-widget .image-block").attr("src", page_params.realm_logo_url);
 
     if (page_params.realm_night_logo_source === "D" && page_params.realm_logo_source !== "D") {
@@ -101,7 +108,7 @@ export function render() {
     );
 }
 
-export function initialize() {
+export function initialize(): void {
     // render once
     render();