diff --git a/pkg/pub_integration/pubspec.yaml b/pkg/pub_integration/pubspec.yaml
index 93ee7e3514..90f9e57c7e 100644
--- a/pkg/pub_integration/pubspec.yaml
+++ b/pkg/pub_integration/pubspec.yaml
@@ -17,5 +17,6 @@ dependencies:
 
 dev_dependencies:
   coverage: any # test already depends on it
+  markdown: ^7.3.0
   shelf: ^1.4.0
   test: ^1.16.5
diff --git a/pkg/pub_integration/tool/compare_screenshots.dart b/pkg/pub_integration/tool/compare_screenshots.dart
new file mode 100644
index 0000000000..0cb917ebc7
--- /dev/null
+++ b/pkg/pub_integration/tool/compare_screenshots.dart
@@ -0,0 +1,125 @@
+// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:io';
+
+import 'package:markdown/markdown.dart';
+import 'package:path/path.dart' as p;
+
+/// Compares the screenshots from the previous and current test runs.
+/// Uses imagemagick for image processing.
+///
+/// `dart <script.dart> <before-dir> <after-dir> <report-dir>`
+Future<void> main(List<String> args) async {
+  final beforeFiles = await _list(args[0]);
+  final afterFiles = await _list(args[1]);
+
+  final reportDir = Directory(args[2]);
+  await reportDir.create(recursive: true);
+  await _CompareTool(beforeFiles, afterFiles, reportDir)._compare();
+}
+
+class _CompareTool {
+  final Directory _reportDir;
+  final Map<String, File> _beforeFiles;
+  final Map<String, File> _afterFiles;
+  final _report = StringBuffer();
+
+  _CompareTool(
+    this._beforeFiles,
+    this._afterFiles,
+    this._reportDir,
+  );
+
+  Future<void> _compare() async {
+    _report.writeln(
+        'Screenshot comparison report generated at ${DateTime.now().toIso8601String()}.');
+
+    final newFiles = _afterFiles.keys
+        .where((key) => !_beforeFiles.containsKey(key))
+        .toList();
+    if (newFiles.isNotEmpty) {
+      _report.writeln([
+        '',
+        '# New files',
+        newFiles.map((e) => '- `$e`').join('\n'),
+      ].join('\n\n'));
+    }
+
+    final missingFiles = _beforeFiles.keys
+        .where((key) => !_afterFiles.containsKey(key))
+        .toList();
+    if (missingFiles.isNotEmpty) {
+      _report.writeln([
+        '',
+        '# Missing files',
+        missingFiles.map((e) => '- `$e`').join('\n'),
+      ].join('\n\n'));
+    }
+
+    for (final path in _afterFiles.keys) {
+      final after = _afterFiles[path]!;
+      if (!_beforeFiles.containsKey(path)) continue;
+      final before = _beforeFiles[path]!;
+
+      // quick byte-content check
+      final afterBytes = await after.readAsBytes();
+      final beforeBytes = await before.readAsBytes();
+      if (afterBytes.length == beforeBytes.length &&
+          afterBytes.indexed.every((e) => beforeBytes[e.$1] == e.$2)) {
+        continue;
+      }
+
+      final relativeDir = p.dirname(path);
+      final basename = p.basenameWithoutExtension(path);
+      final diffPath =
+          p.join(_reportDir.path, relativeDir, '$basename-diff.png');
+      await File(diffPath).parent.create(recursive: true);
+
+      final pr = await Process.run('compare', [
+        before.path,
+        after.path,
+        diffPath,
+      ]);
+      if (pr.exitCode == 0) continue;
+
+      final beforeFile =
+          File(p.join(_reportDir.path, relativeDir, '$basename-before.png'));
+      await beforeFile.writeAsBytes(beforeBytes);
+      final afterFile =
+          File(p.join(_reportDir.path, relativeDir, '$basename-after.png'));
+      await afterFile.writeAsBytes(afterBytes);
+
+      _report.writeln('`$path`\n');
+      _report.writeln(
+          '![before](${p.join(relativeDir, '$basename-before.png')})\n');
+      _report
+          .writeln('![after](${p.join(relativeDir, '$basename-after.png')})\n');
+      _report
+          .writeln('![diff](${p.join(relativeDir, '$basename-diff.png')})\n');
+      _report.writeln();
+    }
+
+    await _writeIndexHtml();
+  }
+
+  Future<void> _writeIndexHtml() async {
+    await File(p.join(_reportDir.path, 'index.html')).writeAsString([
+      '<html><body>',
+      markdownToHtml(_report.toString()),
+      '</body></html>',
+    ].join('\n'));
+  }
+}
+
+Future<Map<String, File>> _list(String path) async {
+  final map = <String, File>{};
+  await for (final file in Directory(path).list(recursive: true)) {
+    if (file is! File) continue;
+    final rp = p.relative(file.path, from: path);
+    map[rp] = file;
+  }
+  return Map.fromEntries(
+      map.entries.toList()..sort((a, b) => a.key.compareTo(b.key)));
+}