diff --git a/doc/api/crypto.md b/doc/api/crypto.md
index 23ba770af30d8d..73c752af15857b 100644
--- a/doc/api/crypto.md
+++ b/doc/api/crypto.md
@@ -2499,7 +2499,7 @@ If the `'subject'` option is set to `'always'` and if the subject alternative
 name extension either does not exist or does not contain a matching email
 address, the certificate subject is considered.
 
-If the `'subject'` option is set to `'default`', the certificate subject is only
+If the `'subject'` option is set to `'default'`, the certificate subject is only
 considered if the subject alternative name extension either does not exist or
 does not contain any email addresses.