diff --git a/panel/src/helpers/field.test.js b/panel/src/helpers/field.test.ts
similarity index 87%
rename from panel/src/helpers/field.test.js
rename to panel/src/helpers/field.test.ts
index af823b9edc..3f098a5d2c 100644
--- a/panel/src/helpers/field.test.js
+++ b/panel/src/helpers/field.test.ts
@@ -2,6 +2,8 @@ import { describe, expect, it } from "vitest";
 import { form } from "./field";
 
 describe.concurrent("$helper.field.form()", () => {
+	// TODO: Remove once window.panel is globally typed
+	// @ts-expect-error - window.panel is not typed yet
 	// mock the app with the component setup
 	window.panel = {
 		app: {
diff --git a/panel/src/helpers/field.js b/panel/src/helpers/field.ts
similarity index 53%
rename from panel/src/helpers/field.js
rename to panel/src/helpers/field.ts
index b70b55c895..5344df205c 100644
--- a/panel/src/helpers/field.js
+++ b/panel/src/helpers/field.ts
@@ -1,20 +1,24 @@
-import { clone } from "./object.js";
+import { clone } from "./object";
+
+type Field = Record<string, unknown>;
 
 /**
  * Loads the default value for a field definition
  * @unstable
  *
- * @param {Object} field
- * @returns {mixed}
+ * @example
+ * defaultValue({ type: "text", default: "Hello" }) // => "Hello"
+ * defaultValue({ type: "text" }) // => null
  */
-export function defaultValue(field) {
+export function defaultValue(field: Field): unknown {
 	if (field.default !== undefined) {
 		return clone(field.default);
 	}
 
-	const component =
-		window.panel.app.$options.components[`k-${field.type}-field`];
-
+	// TODO: Remove once window.panel is globally typed
+	// @ts-expect-error - window.panel has no type yet
+	const options = window.panel.app.$options;
+	const component = options.components[`k-${field.type}-field`];
 	const valueProp = component?.options.props?.value;
 
 	// if the field has no value prop,
@@ -41,11 +45,12 @@ export function defaultValue(field) {
  * Creates form values for provided fields
  * @unstable
  *
- * @param {Object} fields
- * @returns {Object}
+ * @example
+ * form({ title: { type: "text", default: "Hello" }, age: { type: "number" } })
+ * // => { title: "Hello" }
  */
-export function form(fields) {
-	const form = {};
+export function form(fields: Record<string, Field>): Record<string, unknown> {
+	const form: Record<string, unknown> = {};
 
 	for (const fieldName in fields) {
 		const defaultVal = defaultValue(fields[fieldName]);
@@ -63,11 +68,17 @@ export function form(fields) {
  * and the current form values. Also works for sections.
  * @unstable
  *
- * @param {Object} field - The form field object
- * @param {Object} values - The current form values object
- * @returns {boolean} - Whether the field is visible or not
+ * @example
+ * isVisible({ type: "text", when: { status: "draft" } }, { status: "draft" }) // => true
+ * isVisible({ type: "text", when: { status: "draft" } }, { status: "published" }) // => false
+ *
+ * @param field - The form field object
+ * @param values - The current form values object
  */
-export function isVisible(field, values) {
+export function isVisible(
+	field: Field,
+	values: Record<string, unknown>
+): boolean {
 	if (field.type === "hidden" || field.hidden === true) {
 		return false;
 	}
@@ -76,9 +87,11 @@ export function isVisible(field, values) {
 		return true;
 	}
 
-	for (const key in field.when) {
+	const when = field.when as Record<string, unknown>;
+
+	for (const key in when) {
 		const value = values[key.toLowerCase()];
-		const condition = field.when[key];
+		const condition = when[key];
 
 		// if condition is checking for empty field
 		if (
@@ -100,13 +113,12 @@ export function isVisible(field, values) {
  * Adds proper endpoint and section definitions
  * to subfields for a form field.
  * @unstable
- *
- * @param {object} field
- * @param {object} fields
- * @returns {object}
  */
-export function subfields(field, fields) {
-	let subfields = {};
+export function subfields(
+	field: Field,
+	fields: Record<string, Field>
+): Record<string, Field> {
+	const subfields: Record<string, Field> = {};
 
 	for (const name in fields) {
 		const subfield = fields[name];
@@ -114,10 +126,16 @@ export function subfields(field, fields) {
 		subfield.section = field.name;
 
 		if (field.endpoints) {
+			const endpoints = field.endpoints as {
+				field: string;
+				section: string;
+				model: string;
+			};
+
 			subfield.endpoints = {
-				field: field.endpoints.field + "+" + name,
-				section: field.endpoints.section,
-				model: field.endpoints.model
+				field: endpoints.field + "+" + name,
+				section: endpoints.section,
+				model: endpoints.model
 			};
 		}
 
diff --git a/panel/src/helpers/index.js b/panel/src/helpers/index.js
index ae123d3f17..ed9e1ea077 100644
--- a/panel/src/helpers/index.js
+++ b/panel/src/helpers/index.js
@@ -3,7 +3,7 @@ import clipboard from "./clipboard.js";
 import color from "./color.js";
 import debounce from "./debounce";
 import embed from "./embed";
-import field from "./field.js";
+import field from "./field";
 import file from "./file.js";
 import focus from "./focus.js";
 import isComponent from "./isComponent";