diff --git a/src/Umbraco.Web.UI.Client/src/mocks/data/data-type/data-type.data.ts b/src/Umbraco.Web.UI.Client/src/mocks/data/data-type/data-type.data.ts
index 9103803b11..4308cf874a 100644
--- a/src/Umbraco.Web.UI.Client/src/mocks/data/data-type/data-type.data.ts
+++ b/src/Umbraco.Web.UI.Client/src/mocks/data/data-type/data-type.data.ts
@@ -1049,6 +1049,7 @@ export const data: Array<UmbMockDataTypeModel> = [
 							'Umb.Tiptap.Toolbar.Redo',
 							'Umb.Tiptap.Toolbar.StyleSelect',
 							'Umb.Tiptap.Toolbar.FontFamily',
+							'Umb.Tiptap.Toolbar.FontSize',
 							'Umb.Tiptap.Toolbar.Bold',
 							'Umb.Tiptap.Toolbar.Italic',
 							'Umb.Tiptap.Toolbar.TextAlignLeft',
diff --git a/src/Umbraco.Web.UI.Client/src/packages/tiptap/extensions/manifests.ts b/src/Umbraco.Web.UI.Client/src/packages/tiptap/extensions/manifests.ts
index 3481077c1f..5f0c360227 100644
--- a/src/Umbraco.Web.UI.Client/src/packages/tiptap/extensions/manifests.ts
+++ b/src/Umbraco.Web.UI.Client/src/packages/tiptap/extensions/manifests.ts
@@ -473,6 +473,17 @@ const toolbarExtensions: Array<ManifestTiptapToolbarExtension> = [
 			label: 'Font family',
 		},
 	},
+	{
+		type: 'tiptapToolbarExtension',
+		alias: 'Umb.Tiptap.Toolbar.FontSize',
+		name: 'Font Size Tiptap Extension',
+		element: () => import('./toolbar/font-size-tiptap-toolbar.element.js'),
+		meta: {
+			alias: 'umbFontSize',
+			icon: 'icon-palette',
+			label: 'Font size',
+		},
+	},
 ];
 
 const extensions = [
diff --git a/src/Umbraco.Web.UI.Client/src/packages/tiptap/extensions/toolbar/font-size-tiptap-toolbar.element.ts b/src/Umbraco.Web.UI.Client/src/packages/tiptap/extensions/toolbar/font-size-tiptap-toolbar.element.ts
new file mode 100644
index 0000000000..8fc96a23c0
--- /dev/null
+++ b/src/Umbraco.Web.UI.Client/src/packages/tiptap/extensions/toolbar/font-size-tiptap-toolbar.element.ts
@@ -0,0 +1,54 @@
+import { UmbTiptapToolbarButtonElement } from '../../components/toolbar/tiptap-toolbar-button.element.js';
+import type { UmbCascadingMenuItem } from '../../components/cascading-menu-popover/cascading-menu-popover.element.js';
+import { css, customElement, html, ifDefined } from '@umbraco-cms/backoffice/external/lit';
+
+import '../../components/cascading-menu-popover/cascading-menu-popover.element.js';
+
+@customElement('umb-tiptap-font-size-toolbar-element')
+export class UmbTiptapToolbarFontSizeToolbarElement extends UmbTiptapToolbarButtonElement {
+	#fontSizes = [8, 10, 12, 14, 16, 18, 24, 36, 48];
+
+	#menu: Array<UmbCascadingMenuItem> = this.#fontSizes.map((fontSize) => ({
+		unique: `font-size-${fontSize}pt`,
+		label: `${fontSize}pt`,
+		execute: () =>
+			this.editor
+				?.chain()
+				.focus()
+				.setMark('textStyle', { style: `font-size: ${fontSize}pt;` })
+				.run(),
+	}));
+
+	override render() {
+		const label = this.localize.string(this.manifest?.meta.label);
+		return html`
+			<uui-button compact look="secondary" label=${ifDefined(label)} popovertarget="font-size">
+				<span>${label}</span>
+				<uui-symbol-expand slot="extra" open></uui-symbol-expand>
+			</uui-button>
+			<umb-cascading-menu-popover id="font-size" placement="bottom-start" .items=${this.#menu}>
+			</umb-cascading-menu-popover>
+		`;
+	}
+
+	static override readonly styles = [
+		css`
+			:host {
+				--uui-button-font-weight: normal;
+				--uui-menu-item-flat-structure: 1;
+			}
+
+			uui-button > uui-symbol-expand {
+				margin-left: var(--uui-size-space-4);
+			}
+		`,
+	];
+}
+
+export { UmbTiptapToolbarFontSizeToolbarElement as element };
+
+declare global {
+	interface HTMLElementTagNameMap {
+		'umb-tiptap-font-size-toolbar-element': UmbTiptapToolbarFontSizeToolbarElement;
+	}
+}