diff --git a/CHANGELOG.md b/CHANGELOG.md
index 264984d..d8215be 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - **--verbose** which prints detailed logs.
 
+### Changed
+
+- Selector now case-insensitive, so it selects mp4 and MP4 etc.
+
 ## 🎉 [0.3.2] - 2024-01-14
 
 ### Added
diff --git a/src/helpers/vec_helper.rs b/src/helpers/vec_helper.rs
index a8c7e57..fa800a9 100644
--- a/src/helpers/vec_helper.rs
+++ b/src/helpers/vec_helper.rs
@@ -5,8 +5,9 @@ use regex::Regex;
 /// Returns a vector of PathBufs that match the given file format.
 /// Also filters out files that start with a dot.
 pub fn filter_files(all_files: Vec<PathBuf>, file_format: &str) -> Vec<PathBuf> {
-    let re = Regex::new(format!(r"[\\/][^.\\/][^\\/]*\.{}$", regex::escape(file_format)).as_str())
-        .unwrap();
+    let re: Regex =
+        Regex::new(format!(r"(?i)[\\/][^.\\/][^\\/]*\.{}$", regex::escape(file_format)).as_str())
+            .unwrap();
     let mut filtered_files = Vec::new();
 
     for possible_file_to_merge in all_files {