diff --git a/services/web/config/settings.defaults.js b/services/web/config/settings.defaults.js
index 6edb19e6df..a324330bbd 100644
--- a/services/web/config/settings.defaults.js
+++ b/services/web/config/settings.defaults.js
@@ -710,12 +710,13 @@ module.exports = {
   //   - the doc content
   //   - text ranges spanning the whole doc
   //
-  // There's also overhead required for the JSON encoding and the UTF-8 encoding,
-  // theoretically up to 3 times the max doc length. On the other hand, we don't
-  // want to block the event loop with JSON parsing, so we try to find a
-  // practical compromise.
+  // There's also overhead required for the JSON encoding and the UTF-8
+  // encoding, theoretically up to 6 times the max doc length (e.g. a document
+  // entirely filled with "\u0011" characters). On the other hand, we don't want
+  // to block the event loop with JSON parsing, so we try to find a practical
+  // compromise.
   max_json_request_size:
-    parseInt(process.env.MAX_JSON_REQUEST_SIZE) || 6 * 1024 * 1024, // 6 MB
+    parseInt(process.env.MAX_JSON_REQUEST_SIZE) || 12 * 1024 * 1024, // 12 MB
 
   // Internal configs
   // ----------------