diff --git a/src/header/common/cookie.rs b/src/header/common/cookie.rs
index 6e275446..70f241d1 100644
--- a/src/header/common/cookie.rs
+++ b/src/header/common/cookie.rs
@@ -23,7 +23,7 @@ impl Header for Cookies {
     }
 
     fn parse_header(raw: &[Vec<u8>]) -> Option<Cookies> {
-        let mut cookies = vec![];
+        let mut cookies = Vec::with_capacity(raw.len());
         for cookies_raw in raw.iter() {
             match from_utf8(cookies_raw[]) {
                 Some(cookies_str) => {
@@ -44,7 +44,6 @@ impl Header for Cookies {
             None
         }
     }
-
 }
 
 impl HeaderFormat for Cookies {
diff --git a/src/header/common/set_cookie.rs b/src/header/common/set_cookie.rs
index 93ec2b50..0db48a27 100644
--- a/src/header/common/set_cookie.rs
+++ b/src/header/common/set_cookie.rs
@@ -19,7 +19,7 @@ impl Header for SetCookie {
     }
 
     fn parse_header(raw: &[Vec<u8>]) -> Option<SetCookie> {
-        let mut set_cookies = vec![];
+        let mut set_cookies = Vec::with_capacity(raw.len());
         for set_cookies_raw in raw.iter() {
             match from_utf8(set_cookies_raw[]) {
                 Some(s) if !s.is_empty() => {