diff --git a/src/lang.rs b/src/lang.rs
index e9ee151..97fb56f 100644
--- a/src/lang.rs
+++ b/src/lang.rs
@@ -221,6 +221,8 @@ fn success_parse_unicode_language_id() {
     assert_eq!(Some("Latn".to_string()), result.script);
     assert_eq!(Some("US".to_string()), result.region);
     assert_eq!(Some(vec!["macos".to_string()]), result.variants);
+    let result: UnicodeLanguageIdentifier = "en-Latn-US".parse().unwrap();
+    assert_eq!("en-Latn-US", format!("{}", result));
 }
 
 #[test]
diff --git a/src/locale.rs b/src/locale.rs
index 0442de2..8f550ec 100644
--- a/src/locale.rs
+++ b/src/locale.rs
@@ -1,10 +1,12 @@
 use crate::constants::SEP;
 use crate::errors::ParserError;
-use crate::extensions::{parse_extensions_from_iter, Extensions};
+use crate::extensions::{self, parse_extensions_from_iter, Extensions};
 use crate::lang::{parse_unicode_language_id_from_iter, UnicodeLanguageIdentifier};
 use crate::shared::split_str;
 
 use std::fmt::{self};
+use std::str;
+use std::str::FromStr;
 
 #[derive(Debug)]
 pub struct UnicodeLocaleIdentifier {
@@ -14,14 +16,25 @@ pub struct UnicodeLocaleIdentifier {
 
 impl fmt::Display for UnicodeLocaleIdentifier {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        let mut messages = vec![];
-        messages.push(format!("{}", self.language));
-        messages.push(format!("{}", self.extensions));
-        f.write_str(&messages.join(&SEP.to_string()))?;
+        let mut msg = vec![];
+        msg.push(format!("{}", self.language));
+        let extensions_msg = format!("{}", self.extensions);
+        if !extensions_msg.is_empty() {
+            msg.push(extensions_msg);
+        }
+        f.write_str(&msg.join(&SEP.to_string()))?;
         Ok(())
     }
 }
 
+impl FromStr for UnicodeLocaleIdentifier {
+    type Err = ParserError;
+
+    fn from_str(source: &str) -> Result<Self, Self::Err> {
+        parse_unicode_locale_id(source)
+    }
+}
+
 pub fn parse_unicode_locale_id(locale: &str) -> Result<UnicodeLocaleIdentifier, ParserError> {
     // check empty
     if locale.is_empty() {
@@ -59,6 +72,10 @@ fn success_parse_unicode_locale_id() {
         format!("{}", parse_unicode_locale_id("ja-Latn-JP-macos-U-attr1-kz-value2-t-en-Latn-US-linux-t1-value1-value2-a-vue-rust-x-foo-123")
             .unwrap())
     );
+
+    // FromStr trait implementation
+    let result: UnicodeLocaleIdentifier = "ja-Latn-JP".parse().unwrap();
+    assert_eq!("ja-Latn-JP", format!("{}", result));
 }
 
 #[test]