diff --git a/packages/frontend/src/pages/settings/general.vue b/packages/frontend/src/pages/settings/general.vue
index b42c2f1503..7de29f11e3 100644
--- a/packages/frontend/src/pages/settings/general.vue
+++ b/packages/frontend/src/pages/settings/general.vue
@@ -216,6 +216,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 
 			<MkRadios v-model="fontSize">
 				<template #label>{{ i18n.ts.fontSize }}</template>
+				<option value="-1"><span style="font-size: 12.5px;">Aa</span></option>
 				<option :value="null"><span style="font-size: 14px;">Aa</span></option>
 				<option value="1"><span style="font-size: 15px;">Aa</span></option>
 				<option value="2"><span style="font-size: 16px;">Aa</span></option>
diff --git a/packages/frontend/src/style.scss b/packages/frontend/src/style.scss
index 2eebfdd1a3..8eb287d238 100644
--- a/packages/frontend/src/style.scss
+++ b/packages/frontend/src/style.scss
@@ -110,6 +110,9 @@ html {
 		}
 	}
 
+	&.f--1 {
+		font-size: 12.5px;
+	}
 	&.f-1 {
 		font-size: 15px;
 	}