diff --git a/app/javascript/flavours/glitch/features/alt_text_modal/index.tsx b/app/javascript/flavours/glitch/features/alt_text_modal/index.tsx
index 74aa789e1c..d19f653c0f 100644
--- a/app/javascript/flavours/glitch/features/alt_text_modal/index.tsx
+++ b/app/javascript/flavours/glitch/features/alt_text_modal/index.tsx
@@ -54,7 +54,8 @@ const messages = defineMessages({
   },
 });
 
-const MAX_LENGTH = 1500;
+// TODO: use `description_limit` from the `/api/v2/instance` response
+const MAX_LENGTH = 10000;
 
 type FocalPoint = [number, number];