diff --git a/packages/ubuntu_desktop_installer/lib/pages/confirm/confirm_page.dart b/packages/ubuntu_desktop_installer/lib/pages/confirm/confirm_page.dart
index 32f73aea03..e54fcc2d6a 100644
--- a/packages/ubuntu_desktop_installer/lib/pages/confirm/confirm_page.dart
+++ b/packages/ubuntu_desktop_installer/lib/pages/confirm/confirm_page.dart
@@ -1,4 +1,3 @@
-import 'package:filesize/filesize.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_html/flutter_html.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
@@ -138,12 +137,13 @@ class _PartitionLabel extends StatelessWidget {
   final Partition partition;
   final Partition? original;
 
-  String formatPartition(AppLocalizations lang) {
+  String formatPartition(BuildContext context) {
+    final lang = AppLocalizations.of(context);
     if (partition.resize == true) {
       return lang.writeChangesPartitionResized(
         partition.sysname,
-        filesize(original?.size ?? 0),
-        filesize(partition.size ?? 0),
+        context.formatByteSize(original?.size ?? 0),
+        context.formatByteSize(partition.size ?? 0),
       );
     } else if (partition.wipe != null && partition.mount?.isNotEmpty == true) {
       return lang.writeChangesPartitionFormattedMounted(
@@ -169,9 +169,8 @@ class _PartitionLabel extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    final lang = AppLocalizations.of(context);
     return Html(
-      data: formatPartition(lang),
+      data: formatPartition(context),
       style: {'body': Style(margin: Margins.zero)},
     );
   }
diff --git a/packages/ubuntu_desktop_installer/lib/pages/source/not_enough_disk_space/not_enough_disk_space_page.dart b/packages/ubuntu_desktop_installer/lib/pages/source/not_enough_disk_space/not_enough_disk_space_page.dart
index 70e7c4626b..782e4f7d03 100644
--- a/packages/ubuntu_desktop_installer/lib/pages/source/not_enough_disk_space/not_enough_disk_space_page.dart
+++ b/packages/ubuntu_desktop_installer/lib/pages/source/not_enough_disk_space/not_enough_disk_space_page.dart
@@ -1,6 +1,5 @@
 import 'dart:math';
 
-import 'package:filesize/filesize.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:ubuntu_desktop_installer/installer.dart';
@@ -53,7 +52,7 @@ class NotEnoughDiskSpacePage extends ConsumerWidget {
                         ),
                         const SizedBox(width: 8),
                         Text(
-                          filesize(model.installMinimumSize),
+                          context.formatByteSize(model.installMinimumSize),
                           style: Theme.of(context)
                               .textTheme
                               .bodyLarge!
@@ -70,7 +69,7 @@ class NotEnoughDiskSpacePage extends ConsumerWidget {
                         ),
                         const SizedBox(width: 8),
                         Text(
-                          filesize(model.largestDiskSize),
+                          context.formatByteSize(model.largestDiskSize),
                           style: Theme.of(context)
                               .textTheme
                               .bodyLarge!
diff --git a/packages/ubuntu_desktop_installer/lib/pages/storage/guided_reformat/guided_reformat_page.dart b/packages/ubuntu_desktop_installer/lib/pages/storage/guided_reformat/guided_reformat_page.dart
index 6aecedc897..6ac1567733 100644
--- a/packages/ubuntu_desktop_installer/lib/pages/storage/guided_reformat/guided_reformat_page.dart
+++ b/packages/ubuntu_desktop_installer/lib/pages/storage/guided_reformat/guided_reformat_page.dart
@@ -1,4 +1,3 @@
-import 'package:filesize/filesize.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:flutter_svg/flutter_svg.dart';
@@ -24,13 +23,13 @@ class GuidedReformatPage extends ConsumerWidget {
   }
 
   /// Formats a disk in a pretty way e.g. "sda ATA Maxtor (123 GB)"
-  String prettyFormatDisk(Disk disk) {
+  String prettyFormatDisk(BuildContext context, Disk disk) {
     final fullName = <String?>[
       disk.model,
       disk.vendor,
     ].where((p) => p?.isNotEmpty == true).join(' ');
 
-    final size = filesize(disk.size);
+    final size = context.formatByteSize(disk.size);
     return '${disk.sysname} - $size $fullName';
   }
 
@@ -58,7 +57,8 @@ class GuidedReformatPage extends ConsumerWidget {
                   itemBuilder: (context, index, child) {
                     final disk = model.getDisk(index);
                     return disk != null
-                        ? Text(prettyFormatDisk(disk), key: ValueKey(index))
+                        ? Text(prettyFormatDisk(context, disk),
+                            key: ValueKey(index))
                         : const SizedBox.shrink();
                   },
                 ),
@@ -88,7 +88,7 @@ class GuidedReformatPage extends ConsumerWidget {
                   Text(model.selectedDisk?.sysname ?? ''),
                   const SizedBox(height: kWizardSpacing / 2),
                   Text(
-                    filesize(model.selectedDisk?.size ?? 0),
+                    context.formatByteSize(model.selectedDisk?.size ?? 0),
                     style: Theme.of(context).textTheme.headlineSmall,
                   ),
                 ],
diff --git a/packages/ubuntu_desktop_installer/lib/pages/storage/guided_resize/guided_resize_widgets.dart b/packages/ubuntu_desktop_installer/lib/pages/storage/guided_resize/guided_resize_widgets.dart
index a8dd691bc6..eb63a1073d 100644
--- a/packages/ubuntu_desktop_installer/lib/pages/storage/guided_resize/guided_resize_widgets.dart
+++ b/packages/ubuntu_desktop_installer/lib/pages/storage/guided_resize/guided_resize_widgets.dart
@@ -1,4 +1,3 @@
-import 'package:filesize/filesize.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_html/flutter_html.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
@@ -31,7 +30,7 @@ class StorageSelector extends ConsumerWidget {
     final parts = [
       partition?.sysname,
       if (os != null) os.long,
-      if (partition?.size != null) filesize(partition!.size),
+      if (partition?.size != null) context.formatByteSize(partition!.size!),
     ];
     return parts.join(' - ');
   }
diff --git a/packages/ubuntu_desktop_installer/lib/pages/storage/guided_resize/storage_button.dart b/packages/ubuntu_desktop_installer/lib/pages/storage/guided_resize/storage_button.dart
index 3c56a585e7..9c01695e11 100644
--- a/packages/ubuntu_desktop_installer/lib/pages/storage/guided_resize/storage_button.dart
+++ b/packages/ubuntu_desktop_installer/lib/pages/storage/guided_resize/storage_button.dart
@@ -1,5 +1,5 @@
-import 'package:filesize/filesize.dart';
 import 'package:flutter/material.dart';
+import 'package:ubuntu_localizations/ubuntu_localizations.dart';
 import 'package:ubuntu_wizard/ubuntu_wizard.dart';
 
 import 'storage_icon.dart';
@@ -48,7 +48,7 @@ class StorageButton extends StatelessWidget {
           ),
           const SizedBox(height: kWizardSpacing / 2),
           Text(
-            filesize(size),
+            context.formatByteSize(size),
             style: Theme.of(context).textTheme.headlineSmall,
             overflow: TextOverflow.clip,
             softWrap: false,
diff --git a/packages/ubuntu_desktop_installer/lib/pages/storage/manual/manual_storage_widgets.dart b/packages/ubuntu_desktop_installer/lib/pages/storage/manual/manual_storage_widgets.dart
index fe784cded8..a2783c7032 100644
--- a/packages/ubuntu_desktop_installer/lib/pages/storage/manual/manual_storage_widgets.dart
+++ b/packages/ubuntu_desktop_installer/lib/pages/storage/manual/manual_storage_widgets.dart
@@ -1,5 +1,4 @@
 import 'package:collection/collection.dart';
-import 'package:filesize/filesize.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:scroll_to_index/scroll_to_index.dart';
@@ -150,7 +149,10 @@ class _PartitionLabel extends StatelessWidget {
           crossAxisAlignment: CrossAxisAlignment.start,
           children: [
             Text(title, style: Theme.of(context).textTheme.titleSmall),
-            Text(filesize(size), style: Theme.of(context).textTheme.bodySmall),
+            Text(
+              context.formatByteSize(size),
+              style: Theme.of(context).textTheme.bodySmall,
+            ),
           ],
         ),
       ],
diff --git a/packages/ubuntu_desktop_installer/lib/pages/storage/manual/storage_columns.dart b/packages/ubuntu_desktop_installer/lib/pages/storage/manual/storage_columns.dart
index 56e3849a05..159ce4738f 100644
--- a/packages/ubuntu_desktop_installer/lib/pages/storage/manual/storage_columns.dart
+++ b/packages/ubuntu_desktop_installer/lib/pages/storage/manual/storage_columns.dart
@@ -1,4 +1,3 @@
-import 'package:filesize/filesize.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:subiquity_client/subiquity_client.dart';
@@ -131,7 +130,7 @@ class StorageSizeColumn extends StorageColumn {
             return Text(lang.diskHeadersSize);
           },
           diskBuilder: (context, disk) {
-            return Text(filesize(disk.size));
+            return Text(context.formatByteSize(disk.size));
           },
           gapBuilder: (context, disk, gap) {
             final lang = AppLocalizations.of(context);
@@ -143,13 +142,13 @@ class StorageSizeColumn extends StorageColumn {
                   ? lang.tooManyPrimaryPartitions
                   : '',
               child: Text(
-                filesize(gap.size),
+                context.formatByteSize(gap.size),
                 style: TextStyle(color: color),
               ),
             );
           },
           partitionBuilder: (context, disk, partition) {
-            return Text(filesize(partition.size ?? 0));
+            return Text(context.formatByteSize(partition.size ?? 0));
           },
         );
 }
diff --git a/packages/ubuntu_desktop_installer/lib/pages/storage/manual/storage_selector.dart b/packages/ubuntu_desktop_installer/lib/pages/storage/manual/storage_selector.dart
index 5b8064e97d..504cbfa91f 100644
--- a/packages/ubuntu_desktop_installer/lib/pages/storage/manual/storage_selector.dart
+++ b/packages/ubuntu_desktop_installer/lib/pages/storage/manual/storage_selector.dart
@@ -1,6 +1,6 @@
-import 'package:filesize/filesize.dart';
 import 'package:flutter/material.dart';
 import 'package:subiquity_client/subiquity_client.dart';
+import 'package:ubuntu_localizations/ubuntu_localizations.dart';
 import 'package:ubuntu_widgets/ubuntu_widgets.dart';
 
 class StorageSelector extends StatelessWidget {
@@ -26,7 +26,7 @@ class StorageSelector extends StatelessWidget {
         storage.model,
         storage.vendor,
       ].where((p) => p?.isNotEmpty == true).join(' ');
-      return '${storage.sysname} $fullName (${filesize(storage.size)})';
+      return '${storage.sysname} $fullName (${context.formatByteSize(storage.size)})';
     }
 
     return Column(
diff --git a/packages/ubuntu_desktop_installer/lib/pages/storage/manual/storage_types.dart b/packages/ubuntu_desktop_installer/lib/pages/storage/manual/storage_types.dart
index ccc5aefc8a..68b6b76d67 100644
--- a/packages/ubuntu_desktop_installer/lib/pages/storage/manual/storage_types.dart
+++ b/packages/ubuntu_desktop_installer/lib/pages/storage/manual/storage_types.dart
@@ -1,4 +1,3 @@
-import 'package:filesize/filesize.dart';
 import 'package:subiquity_client/subiquity_client.dart';
 
 export 'package:subiquity_client/subiquity_client.dart'
@@ -9,16 +8,11 @@ extension GapExtension on Gap {
       usable == GapUsable.TOO_MANY_PRIMARY_PARTS;
 }
 
-extension DiskExtension on Disk {
-  String get prettySize => filesize(size);
-}
-
 extension PartitionExtension on Partition {
   bool get canWipe => PartitionFormat.fromPartition(this)?.canWipe == true;
   bool get canEdit => format != 'BitLocker';
   bool get isEncrypted => format == 'BitLocker';
   bool get isWiped => wipe == 'superblock';
-  String get prettySize => filesize(size ?? 0);
   bool mustWipe(String? format) {
     // a preserved partition must be wiped if its format changed
     return preserve == true && format != null && this.format != format;
diff --git a/packages/ubuntu_desktop_installer/pubspec.yaml b/packages/ubuntu_desktop_installer/pubspec.yaml
index 95073a9098..11e4faeb6e 100644
--- a/packages/ubuntu_desktop_installer/pubspec.yaml
+++ b/packages/ubuntu_desktop_installer/pubspec.yaml
@@ -15,7 +15,6 @@ dependencies:
   dbus: ^0.7.3
   diacritic: ^0.1.3
   file: ^6.1.0
-  filesize: ^2.0.0
   flutter:
     sdk: flutter
   flutter_html: 3.0.0-beta.1
diff --git a/packages/ubuntu_desktop_installer/test/confirm/confirm_page_test.dart b/packages/ubuntu_desktop_installer/test/confirm/confirm_page_test.dart
index 1031c694a5..151e88be1a 100644
--- a/packages/ubuntu_desktop_installer/test/confirm/confirm_page_test.dart
+++ b/packages/ubuntu_desktop_installer/test/confirm/confirm_page_test.dart
@@ -1,4 +1,3 @@
-import 'package:filesize/filesize.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_test/flutter_test.dart';
 import 'package:mockito/mockito.dart';
@@ -112,8 +111,8 @@ void main() {
         find.html(tester.lang.writeChangesPartitionMounted('sdb5', '/mnt/5')),
         findsOneWidget);
     expect(
-        find.html(tester.lang
-            .writeChangesPartitionResized('sdb6', filesize(123), filesize(66))),
+        find.html(
+            tester.lang.writeChangesPartitionResized('sdb6', '123 B', '66 B')),
         findsOneWidget);
     expect(find.html(tester.lang.writeChangesPartitionCreated('sdb7')),
         findsOneWidget);
diff --git a/packages/ubuntu_desktop_installer/test/source/not_enough_disk_space/not_enough_disk_space_page_test.dart b/packages/ubuntu_desktop_installer/test/source/not_enough_disk_space/not_enough_disk_space_page_test.dart
index 857ec70cec..4d0077ec5f 100644
--- a/packages/ubuntu_desktop_installer/test/source/not_enough_disk_space/not_enough_disk_space_page_test.dart
+++ b/packages/ubuntu_desktop_installer/test/source/not_enough_disk_space/not_enough_disk_space_page_test.dart
@@ -1,7 +1,7 @@
-import 'package:filesize/filesize.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:flutter_test/flutter_test.dart';
+import 'package:ubuntu_desktop_installer/l10n.dart';
 import 'package:ubuntu_desktop_installer/pages/source/not_enough_disk_space/not_enough_disk_space_model.dart';
 import 'package:ubuntu_desktop_installer/pages/source/not_enough_disk_space/not_enough_disk_space_page.dart';
 import 'package:yaru_test/yaru_test.dart';
@@ -25,10 +25,11 @@ void main() {
         largestDiskSize: 123456, installMinimumSize: 654321);
     await tester.pumpWidget(tester.buildApp((_) => buildPage(model)));
 
+    final context = tester.element(find.byType(NotEnoughDiskSpacePage));
     expect(find.text(tester.lang.notEnoughDiskSpaceUbuntu('Ubuntu')),
         findsOneWidget);
-    expect(find.text(filesize(123456)), findsOneWidget);
-    expect(find.text(filesize(654321)), findsOneWidget);
+    expect(find.text(context.formatByteSize(123456)), findsOneWidget);
+    expect(find.text(context.formatByteSize(654321)), findsOneWidget);
   });
 
   testWidgets('quit', (tester) async {
diff --git a/packages/ubuntu_desktop_installer/test/storage/guided_reformat/guided_reformat_page_test.dart b/packages/ubuntu_desktop_installer/test/storage/guided_reformat/guided_reformat_page_test.dart
index 9affdc469a..08be556544 100644
--- a/packages/ubuntu_desktop_installer/test/storage/guided_reformat/guided_reformat_page_test.dart
+++ b/packages/ubuntu_desktop_installer/test/storage/guided_reformat/guided_reformat_page_test.dart
@@ -1,4 +1,3 @@
-import 'package:filesize/filesize.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:flutter_test/flutter_test.dart';
@@ -7,6 +6,7 @@ import 'package:subiquity_client/subiquity_client.dart';
 import 'package:subiquity_test/subiquity_test.dart';
 import 'package:ubuntu_desktop_installer/pages/storage/guided_reformat/guided_reformat_model.dart';
 import 'package:ubuntu_desktop_installer/pages/storage/guided_reformat/guided_reformat_page.dart';
+import 'package:ubuntu_localizations/ubuntu_localizations.dart';
 import 'package:ubuntu_test/ubuntu_test.dart';
 import 'package:ubuntu_widgets/ubuntu_widgets.dart';
 
@@ -80,7 +80,9 @@ void main() {
     );
     await tester.pumpWidget(tester.buildApp((_) => buildPage(model)));
     expect(find.text(selectedDisk.sysname), findsOneWidget);
-    expect(find.text(filesize(selectedDisk.size)), findsOneWidget);
+    final context = tester.element(find.byType(GuidedReformatPage));
+    expect(
+        find.text(context.formatByteSize(selectedDisk.size)), findsOneWidget);
   });
 
   testWidgets('saves guided storage', (tester) async {
diff --git a/packages/ubuntu_desktop_installer/test/storage/manual/manual_storage_page_test.dart b/packages/ubuntu_desktop_installer/test/storage/manual/manual_storage_page_test.dart
index df747efd98..2ee6559e82 100644
--- a/packages/ubuntu_desktop_installer/test/storage/manual/manual_storage_page_test.dart
+++ b/packages/ubuntu_desktop_installer/test/storage/manual/manual_storage_page_test.dart
@@ -1,4 +1,3 @@
-import 'package:filesize/filesize.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 import 'package:flutter_test/flutter_test.dart';
@@ -9,6 +8,7 @@ import 'package:ubuntu_desktop_installer/pages/storage/manual/manual_storage_mod
 import 'package:ubuntu_desktop_installer/pages/storage/manual/manual_storage_page.dart';
 import 'package:ubuntu_desktop_installer/pages/storage/manual/storage_selector.dart';
 import 'package:ubuntu_desktop_installer/services.dart';
+import 'package:ubuntu_localizations/ubuntu_localizations.dart';
 import 'package:ubuntu_test/ubuntu_test.dart';
 import 'package:yaru_icons/yaru_icons.dart';
 import 'package:yaru_test/yaru_test.dart';
@@ -78,14 +78,16 @@ void main() {
     final model = buildManualStorageModel(disks: testDisks);
     await tester.pumpWidget(tester.buildApp((_) => buildPage(model)));
 
+    final context = tester.element(find.byType(ManualStoragePage));
     for (final disk in testDisks) {
       expect(find.text(disk.sysname), findsOneWidget);
-      expect(find.text(filesize(disk.size)), findsOneWidget);
+      expect(find.text(context.formatByteSize(disk.size)), findsOneWidget);
 
       for (final partition in disk.partitions.whereType<Partition>()) {
         expect(find.text(partition.format!), findsOneWidget);
         expect(find.text(partition.mount!), findsOneWidget);
-        expect(find.text(filesize(partition.size!)), findsOneWidget);
+        expect(
+            find.text(context.formatByteSize(partition.size!)), findsOneWidget);
       }
     }
   });