diff --git a/app/controllers/admin/backups_controller.rb b/app/controllers/admin/backups_controller.rb
index a80e1b924d4..83587ac3bb9 100644
--- a/app/controllers/admin/backups_controller.rb
+++ b/app/controllers/admin/backups_controller.rb
@@ -110,7 +110,7 @@ class Admin::BackupsController < Admin::AdminController
     filename   = params.fetch(:resumableFilename)
     total_size = params.fetch(:resumableTotalSize).to_i
 
-    return render status: 415, text: I18n.t("backup.backup_file_should_be_tar_gz") unless filename.to_s.end_with?(".tar.gz")
+    return render status: 415, text: I18n.t("backup.backup_file_should_be_tar_gz") unless /\.(tar\.gz|t?gz)$/i =~ filename
     return render status: 415, text: I18n.t("backup.not_enough_space_on_disk")     unless has_enough_space_on_disk?(total_size)
 
     file               = params.fetch(:file)
diff --git a/app/models/backup.rb b/app/models/backup.rb
index 8b2b27d8064..c143eeb10c7 100644
--- a/app/models/backup.rb
+++ b/app/models/backup.rb
@@ -10,7 +10,7 @@ class Backup
   end
 
   def self.all
-    Dir.glob(File.join(Backup.base_directory, "*.tar.gz"))
+    Dir.glob(File.join(Backup.base_directory, "*.{gz,tgz}"))
        .sort_by { |file| File.mtime(file) }
        .reverse
        .map { |backup| Backup.create_from_filename(File.basename(backup)) }
diff --git a/config/routes.rb b/config/routes.rb
index ebac63bacfd..731838d2e70 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -8,7 +8,7 @@ require_dependency "permalink_constraint"
 # This used to be User#username_format, but that causes a preload of the User object
 # and makes Guard not work properly.
 USERNAME_ROUTE_FORMAT = /[A-Za-z0-9\_]+/ unless defined? USERNAME_ROUTE_FORMAT
-BACKUP_ROUTE_FORMAT = /[a-zA-Z0-9\-_]*\d{4}(-\d{2}){2}-\d{6}\.tar\.gz/i unless defined? BACKUP_ROUTE_FORMAT
+BACKUP_ROUTE_FORMAT = /[a-zA-Z0-9\-_]*\d{4}(-\d{2}){2}-\d{6}\.(tar\.gz|t?gz)/i unless defined? BACKUP_ROUTE_FORMAT
 
 Discourse::Application.routes.draw do