diff --git a/CHANGELOG.md b/CHANGELOG.md
index c7b9d5d..53c712c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,8 @@
+## 0.2.4
+
+* Add support for "sniffing" the content of the file for the content-type via an optional
+  `useHeaderBytesForContentType` argument on `createStaticHandler`.
+
 ## 0.2.3+4
 
 * Support `http_parser` 3.0.0.
diff --git a/lib/src/static_handler.dart b/lib/src/static_handler.dart
index 725c438..a2a1b5c 100644
--- a/lib/src/static_handler.dart
+++ b/lib/src/static_handler.dart
@@ -3,7 +3,9 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:io';
+import 'dart:math' as math;
 
+import 'package:convert/convert.dart';
 import 'package:http_parser/http_parser.dart';
 import 'package:mime/mime.dart' as mime;
 import 'package:path/path.dart' as p;
@@ -28,13 +30,13 @@
 /// If no [defaultDocument] is found and [listDirectories] is true, then the
 /// handler produces a listing of the directory.
 ///
-/// If [useHeaderBytesForContentType] is set to false, then the content type will
-/// be determined by the file's extension, as is the mime library's default behavior.
-/// Setting it to true will cause up tot he first 25 bytes of the file to be read
-/// and used to determine the content type.
+/// If [useHeaderBytesForContentType] is `true`, the contents of the
+/// file will be used along with the file path to determine the content type.
 Handler createStaticHandler(String fileSystemPath,
-    {bool serveFilesOutsidePath: false, String defaultDocument,
-    bool listDirectories: false, bool useHeaderBytesForContentType: false}) {
+    {bool serveFilesOutsidePath: false,
+    String defaultDocument,
+    bool listDirectories: false,
+    bool useHeaderBytesForContentType: false}) {
   var rootDir = new Directory(fileSystemPath);
   if (!rootDir.existsSync()) {
     throw new ArgumentError('A directory corresponding to fileSystemPath '
@@ -105,15 +107,16 @@
       HttpHeaders.LAST_MODIFIED: formatHttpDate(fileStat.changed)
     };
 
+    String contentType;
+    if (useHeaderBytesForContentType) {
+      var length =
+          math.min(mime.defaultMagicNumbersMaxLength, file.lengthSync());
 
-    var contentType;
-    if(useHeaderBytesForContentType) {
-      int length = 25; // The longest file header identifier
-      int file_length =file.lengthSync();
-      if(file_length<length)
-        length = file_length;
-      List<int> magicBytes = await file.openRead(0,length).single;
-      contentType = mime.lookupMimeType(file.path, headerBytes: magicBytes);
+      var byteSink = new ByteAccumulatorSink();
+
+      await file.openRead(0, length).listen(byteSink.add).asFuture();
+
+      contentType = mime.lookupMimeType(file.path, headerBytes: byteSink.bytes);
     } else {
       contentType = mime.lookupMimeType(file.path);
     }
diff --git a/pubspec.yaml b/pubspec.yaml
index 6396da8..f1cc8d4 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,11 +1,12 @@
 name: shelf_static
-version: 0.2.3+4
+version: 0.2.4
 author: Dart Team <misc@dartlang.org>
 description: Static file server support for Shelf
 homepage: https://github.com/dart-lang/shelf_static
 environment:
   sdk: '>=1.7.0 <2.0.0'
 dependencies:
+  convert: '>=1.0.0 <3.0.0'
   http_parser: '>=0.0.2+2 <4.0.0'
   mime: '>=0.9.0 <0.10.0'
   path: '>=1.1.0 <2.0.0'
diff --git a/test/basic_file_test.dart b/test/basic_file_test.dart
index 3de28f1..8348761 100644
--- a/test/basic_file_test.dart
+++ b/test/basic_file_test.dart
@@ -25,13 +25,20 @@
     d.file('index.html', '<html></html>').create();
     d.file('root.txt', 'root txt').create();
     d.file('random.unknown', 'no clue').create();
-    d.binaryFile('header_bytes_test_image', BASE64.decode(r"iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACNbyblAAAABmJLR0QA/wD/AP+gvaeTAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH4AYRETkSXaxBzQAAAB1pVFh0Q29tbWVudAAAAAAAQ3JlYXRlZCB3aXRoIEdJTVBkLmUHAAAAbUlEQVQI1wXBvwpBYRwA0HO/kjBKJmXRLWXxJ4PsnsMTeAEPILvNZrybF7B4A6XvQW6k+DkHwqgM1TnMpoEoDMtwOJE7pB/VXmF3CdseucmjxaAruR41Pl9p/Gbyoq5B9FeL2OR7zJ+3aC/X8QdQCyIArPsHkQAAAABJRU5ErkJggg==")).create();
-    d
-        .dir('files', [
+
+    var pngBytesContent =
+        r"iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAYAAACNbyblAAAABmJLR0QA/wD/AP+gvae"
+        r"TAAAACXBIWXMAAAsTAAALEwEAmpwYAAAAB3RJTUUH4AYRETkSXaxBzQAAAB1pVFh0Q2"
+        r"9tbWVudAAAAAAAQ3JlYXRlZCB3aXRoIEdJTVBkLmUHAAAAbUlEQVQI1wXBvwpBYRwA0"
+        r"HO/kjBKJmXRLWXxJ4PsnsMTeAEPILvNZrybF7B4A6XvQW6k+DkHwqgM1TnMpoEoDMtw"
+        r"OJE7pB/VXmF3CdseucmjxaAruR41Pl9p/Gbyoq5B9FeL2OR7zJ+3aC/X8QdQCyIArPs"
+        r"HkQAAAABJRU5ErkJggg==";
+
+    d.dir('files', [
       d.file('test.txt', 'test txt content'),
-      d.file('with space.txt', 'with space content')
-    ])
-        .create();
+      d.file('with space.txt', 'with space content'),
+      d.binaryFile('header_bytes_test_image', BASE64.decode(pngBytesContent))
+    ]).create();
 
     currentSchedule.onComplete.schedule(() {
       d.defaultRoot = null;
@@ -202,9 +209,11 @@
 
     test('magic_bytes_test_image should be image/png', () {
       schedule(() {
-        var handler = createStaticHandler(d.defaultRoot, useHeaderBytesForContentType: true);
+        var handler = createStaticHandler(d.defaultRoot,
+            useHeaderBytesForContentType: true);
 
-        return makeRequest(handler, '/header_bytes_test_image').then((response) {
+        return makeRequest(handler, '/files/header_bytes_test_image')
+            .then((response) {
           expect(response.mimeType, "image/png");
         });
       });