diff --git a/src/html.rs b/src/html.rs
index c0e291d..9f4a4f0 100644
--- a/src/html.rs
+++ b/src/html.rs
@@ -473,7 +473,7 @@ pub fn walk_and_embed_assets(
                             );
                             let mut buf: Vec<u8> = Vec::new();
                             serialize(&mut buf, &dom.document, SerializeOpts::default()).unwrap();
-                            let iframe_data_url = data_to_data_url("text/html", &buf);
+                            let iframe_data_url = data_to_data_url("text/html", &buf, "");
                             attr.value.clear();
                             attr.value.push_slice(iframe_data_url.as_str());
                         }
diff --git a/src/tests/utils/data_to_data_url.rs b/src/tests/utils/data_to_data_url.rs
index bccdf77..b5ed0ca 100644
--- a/src/tests/utils/data_to_data_url.rs
+++ b/src/tests/utils/data_to_data_url.rs
@@ -11,7 +11,7 @@ use crate::utils;
 fn passing_encode_string_with_specific_media_type() {
     let mime = "application/javascript";
     let data = "var word = 'hello';\nalert(word);\n";
-    let data_url = utils::data_to_data_url(mime, data.as_bytes());
+    let data_url = utils::data_to_data_url(mime, data.as_bytes(), "");
 
     assert_eq!(
         &data_url,
diff --git a/src/tests/utils/detect_media_type.rs b/src/tests/utils/detect_media_type.rs
index 99dc51f..6dee71c 100644
--- a/src/tests/utils/detect_media_type.rs
+++ b/src/tests/utils/detect_media_type.rs
@@ -8,40 +8,130 @@ use crate::utils;
 //  ╚═╝     ╚═╝  ╚═╝╚══════╝╚══════╝╚═╝╚═╝  ╚═══╝ ╚═════╝
 
 #[test]
-fn passing_image_media_types() {
-    assert_eq!(utils::detect_media_type(b"GIF87a"), "image/gif");
-    assert_eq!(utils::detect_media_type(b"GIF89a"), "image/gif");
-    assert_eq!(utils::detect_media_type(b"\xFF\xD8\xFF"), "image/jpeg");
+fn passing_image_gif87() {
+    assert_eq!(utils::detect_media_type(b"GIF87a", ""), "image/gif");
+}
+
+#[test]
+fn passing_image_gif89() {
+    assert_eq!(utils::detect_media_type(b"GIF89a", ""), "image/gif");
+}
+
+#[test]
+fn passing_image_jpeg() {
+    assert_eq!(utils::detect_media_type(b"\xFF\xD8\xFF", ""), "image/jpeg");
+}
+
+#[test]
+fn passing_image_png() {
     assert_eq!(
-        utils::detect_media_type(b"\x89PNG\x0D\x0A\x1A\x0A"),
+        utils::detect_media_type(b"\x89PNG\x0D\x0A\x1A\x0A", ""),
         "image/png"
     );
-    assert_eq!(utils::detect_media_type(b"<?xml "), "image/svg+xml");
-    assert_eq!(utils::detect_media_type(b"<svg "), "image/svg+xml");
-    assert_eq!(utils::detect_media_type(b"RIFF....WEBPVP8 "), "image/webp");
+}
+
+#[test]
+fn passing_image_svg() {
+    assert_eq!(utils::detect_media_type(b"<svg ", ""), "image/svg+xml");
+}
+
+#[test]
+fn passing_image_webp() {
     assert_eq!(
-        utils::detect_media_type(b"\x00\x00\x01\x00"),
+        utils::detect_media_type(b"RIFF....WEBPVP8 ", ""),
+        "image/webp"
+    );
+}
+
+#[test]
+fn passing_image_icon() {
+    assert_eq!(
+        utils::detect_media_type(b"\x00\x00\x01\x00", ""),
         "image/x-icon"
     );
 }
 
 #[test]
-fn passing_audio_media_types() {
-    assert_eq!(utils::detect_media_type(b"ID3"), "audio/mpeg");
-    assert_eq!(utils::detect_media_type(b"\xFF\x0E"), "audio/mpeg");
-    assert_eq!(utils::detect_media_type(b"\xFF\x0F"), "audio/mpeg");
-    assert_eq!(utils::detect_media_type(b"OggS"), "audio/ogg");
-    assert_eq!(utils::detect_media_type(b"RIFF....WAVEfmt "), "audio/wav");
-    assert_eq!(utils::detect_media_type(b"fLaC"), "audio/x-flac");
+fn passing_image_svg_filename() {
+    assert_eq!(
+        utils::detect_media_type(b"<?xml ", "local-file.svg"),
+        "image/svg+xml"
+    );
+}
+
+#[test]
+fn passing_image_svg_url_uppercase() {
+    assert_eq!(
+        utils::detect_media_type(b"", "https://some-site.com/images/local-file.SVG"),
+        "image/svg+xml"
+    );
+}
+
+#[test]
+fn passing_audio_mpeg() {
+    assert_eq!(utils::detect_media_type(b"ID3", ""), "audio/mpeg");
+}
+
+#[test]
+fn passing_audio_mpeg_2() {
+    assert_eq!(utils::detect_media_type(b"\xFF\x0E", ""), "audio/mpeg");
 }
 
 #[test]
-fn passing_video_media_types() {
-    assert_eq!(utils::detect_media_type(b"RIFF....AVI LIST"), "video/avi");
-    assert_eq!(utils::detect_media_type(b"....ftyp"), "video/mp4");
-    assert_eq!(utils::detect_media_type(b"\x00\x00\x01\x0B"), "video/mpeg");
-    assert_eq!(utils::detect_media_type(b"....moov"), "video/quicktime");
-    assert_eq!(utils::detect_media_type(b"\x1A\x45\xDF\xA3"), "video/webm");
+fn passing_audio_mpeg_3() {
+    assert_eq!(utils::detect_media_type(b"\xFF\x0F", ""), "audio/mpeg");
+}
+
+#[test]
+fn passing_audio_ogg() {
+    assert_eq!(utils::detect_media_type(b"OggS", ""), "audio/ogg");
+}
+
+#[test]
+fn passing_audio_wav() {
+    assert_eq!(
+        utils::detect_media_type(b"RIFF....WAVEfmt ", ""),
+        "audio/wav"
+    );
+}
+
+#[test]
+fn passing_audio_flac() {
+    assert_eq!(utils::detect_media_type(b"fLaC", ""), "audio/x-flac");
+}
+
+#[test]
+fn passing_video_avi() {
+    assert_eq!(
+        utils::detect_media_type(b"RIFF....AVI LIST", ""),
+        "video/avi"
+    );
+}
+
+#[test]
+fn passing_video_mp4() {
+    assert_eq!(utils::detect_media_type(b"....ftyp", ""), "video/mp4");
+}
+
+#[test]
+fn passing_video_mpeg() {
+    assert_eq!(
+        utils::detect_media_type(b"\x00\x00\x01\x0B", ""),
+        "video/mpeg"
+    );
+}
+
+#[test]
+fn passing_video_quicktime() {
+    assert_eq!(utils::detect_media_type(b"....moov", ""), "video/quicktime");
+}
+
+#[test]
+fn passing_video_webm() {
+    assert_eq!(
+        utils::detect_media_type(b"\x1A\x45\xDF\xA3", ""),
+        "video/webm"
+    );
 }
 
 //  ███████╗ █████╗ ██╗██╗     ██╗███╗   ██╗ ██████╗
@@ -53,5 +143,5 @@ fn passing_video_media_types() {
 
 #[test]
 fn failing_unknown_media_type() {
-    assert_eq!(utils::detect_media_type(b"abcdef0123456789"), "");
+    assert_eq!(utils::detect_media_type(b"abcdef0123456789", ""), "");
 }
diff --git a/src/tests/utils/resolve_url.rs b/src/tests/utils/resolve_url.rs
index ab62f8f..c9090ce 100644
--- a/src/tests/utils/resolve_url.rs
+++ b/src/tests/utils/resolve_url.rs
@@ -111,6 +111,21 @@ fn passing_from_data_url_to_https() -> Result<(), ParseError> {
     Ok(())
 }
 
+#[test]
+fn passing_from_data_url_to_data_url() -> Result<(), ParseError> {
+    let resolved_url = utils::resolve_url(
+        "data:text/html;base64,V2VsY29tZSBUbyBUaGUgUGFydHksIDxiPlBhbDwvYj4h",
+        "data:text/html;base64,PGEgaHJlZj0iaW5kZXguaHRtbCI+SG9tZTwvYT4K",
+    )?;
+
+    assert_eq!(
+        resolved_url.as_str(),
+        "data:text/html;base64,PGEgaHJlZj0iaW5kZXguaHRtbCI+SG9tZTwvYT4K"
+    );
+
+    Ok(())
+}
+
 #[test]
 fn passing_from_file_url_to_relative_path() -> Result<(), ParseError> {
     let resolved_url = utils::resolve_url(
diff --git a/src/utils.rs b/src/utils.rs
index 13ba70f..8b5398b 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -42,13 +42,12 @@ lazy_static! {
     static ref REGEX_CSS_URL: Regex = Regex::new(CSS_URL_REGEX_STR).unwrap();
 }
 
-const MAGIC: [[&[u8]; 2]; 19] = [
+const MAGIC: [[&[u8]; 2]; 18] = [
     // Image
     [b"GIF87a", b"image/gif"],
     [b"GIF89a", b"image/gif"],
     [b"\xFF\xD8\xFF", b"image/jpeg"],
     [b"\x89PNG\x0D\x0A\x1A\x0A", b"image/png"],
-    [b"<?xml ", b"image/svg+xml"],
     [b"<svg ", b"image/svg+xml"],
     [b"RIFF....WEBPVP8 ", b"image/webp"],
     [b"\x00\x00\x01\x00", b"image/x-icon"],
@@ -67,21 +66,26 @@ const MAGIC: [[&[u8]; 2]; 19] = [
     [b"\x1A\x45\xDF\xA3", b"video/webm"],
 ];
 
-pub fn data_to_data_url(mime: &str, data: &[u8]) -> String {
-    let media_type = if mime.is_empty() {
-        detect_media_type(data)
+pub fn data_to_data_url(media_type: &str, data: &[u8], url: &str) -> String {
+    let media_type = if media_type.is_empty() {
+        detect_media_type(data, &url)
     } else {
-        mime.to_string()
+        media_type.to_string()
     };
     format!("data:{};base64,{}", media_type, base64::encode(data))
 }
 
-pub fn detect_media_type(data: &[u8]) -> String {
+pub fn detect_media_type(data: &[u8], url: &str) -> String {
     for item in MAGIC.iter() {
         if data.starts_with(item[0]) {
             return String::from_utf8(item[1].to_vec()).unwrap();
         }
     }
+
+    if url.to_lowercase().ends_with(".svg") {
+        return str!("image/svg+xml");
+    }
+
     str!()
 }
 
@@ -179,7 +183,7 @@ pub fn resolve_css_imports(
                 &parent_url,
                 &embedded_url,
                 true, // Format as data URL
-                "",   // Unknown MIME type
+                "",   // Unknown media type
                 opt_silent,
             )
             .map(|(a, _)| a)
@@ -206,7 +210,7 @@ pub fn resolve_css_imports(
     }
 
     if as_data_url {
-        data_to_data_url("text/css", resolved_css.as_bytes())
+        data_to_data_url("text/css", resolved_css.as_bytes(), "")
     } else {
         resolved_css
     }
@@ -214,8 +218,10 @@ pub fn resolve_css_imports(
 
 pub fn clean_url<T: AsRef<str>>(url: T) -> String {
     let mut result = Url::parse(url.as_ref()).unwrap();
+
     // Clear fragment
     result.set_fragment(None);
+
     // Get rid of stray question mark
     if result.query() == Some("") {
         result.set_query(None);
@@ -238,14 +244,14 @@ pub fn data_url_to_text<T: AsRef<str>>(url: T) -> String {
     let data: String = decode_url(raw_data);
 
     let meta_data_items: Vec<&str> = meta_data.split(';').collect();
-    let mut mime_type: &str = "";
+    let mut media_type: &str = "";
     let mut encoding: &str = "";
 
     let mut i: i8 = 0;
     for item in &meta_data_items {
         if i == 0 {
             if item.eq_ignore_ascii_case("text/html") {
-                mime_type = item;
+                media_type = item;
                 continue;
             }
         }
@@ -257,7 +263,7 @@ pub fn data_url_to_text<T: AsRef<str>>(url: T) -> String {
         i = i + 1;
     }
 
-    if mime_type.eq_ignore_ascii_case("text/html") {
+    if media_type.eq_ignore_ascii_case("text/html") {
         if encoding.eq_ignore_ascii_case("base64") {
             String::from_utf8(base64::decode(&data).unwrap_or(vec![])).unwrap_or(str!())
         } else {
@@ -291,7 +297,7 @@ pub fn retrieve_asset(
     parent_url: &str,
     url: &str,
     as_data_url: bool,
-    mime: &str,
+    media_type: &str,
     opt_silent: bool,
 ) -> Result<(String, String), reqwest::Error> {
     if url.len() == 0 {
@@ -318,7 +324,11 @@ pub fn retrieve_asset(
             }
 
             if as_data_url {
-                let data_url: String = data_to_data_url(&mime, &fs::read(&fs_file_path).unwrap());
+                let data_url: String = data_to_data_url(
+                    &media_type,
+                    &fs::read(&fs_file_path).unwrap(),
+                    &fs_file_path,
+                );
                 Ok((data_url, url.to_string()))
             } else {
                 let data: String = fs::read_to_string(&fs_file_path).expect(url);
@@ -355,17 +365,17 @@ pub fn retrieve_asset(
                 let mut data: Vec<u8> = vec![];
                 response.copy_to(&mut data)?;
 
-                // Attempt to obtain MIME type by reading the Content-Type header
-                let media_type = if mime == "" {
+                // Attempt to obtain media type by reading the Content-Type header
+                let media_type = if media_type == "" {
                     response
                         .headers()
                         .get(CONTENT_TYPE)
                         .and_then(|header| header.to_str().ok())
-                        .unwrap_or(&mime)
+                        .unwrap_or(&media_type)
                 } else {
-                    mime
+                    media_type
                 };
-                let data_url = data_to_data_url(&media_type, &data);
+                let data_url = data_to_data_url(&media_type, &data, url);
                 // Add to cache
                 cache.insert(new_cache_key, data_url.clone());
                 Ok((data_url, res_url))