Naru's Flexible Renamer is a free tool for renaming files and folders, either singly or in large batches, including subfolders. It can rename items using a wide range of methods: copying, substituting, translating, moving, reordering, and attaching letters, numbers, and characters in specified or randomly generated patterns. It also supports Unicode strings for a wide range of languages. It has sophisticated, flexible filtering options to exclude or include items for processing, and it can modify file or folder information such as time and date stamp.

Flexible Renamer is a portable application that doesn't have to be installed: just click it and it runs. It uses an interesting and efficient variation on the typical Windows interface, with the usual left-hand Explorer panel and right-hand main view separated by a panel of controls, including a menu of commands, some filter options, and the Rename buttons. The main view has a customizable gridded display that shows the current name, new name, location, and other information about selected items. Since by far most people want a file renamer to manage the gigabytes of digital snapshots they upload, we started with some of our own. We browsed to a target folder and its contents appeared in the main view. In the central panel, we clicked Remove Number or String, and the selection expanded with many specific options. We made our selections, clicked Rename, and the renamed files appeared in the main view. We clicked Advanced Rename, and controls and selections appeared for Wild Card, Regular Expression, and Translation methods with search fields and numerous Presets and Support settings, the latter enabling a huge range of matches; there's even an email link to request new matches. The Advanced Renaming option proved easy to use for special instances, like renaming a batch of files to fit in a previously defined sequence. We also like the Tag Rename option, which lets you label files with information such as their type (MP3, EXIF, etc.) as well as the Attributes tab, which we used to change the date stamp to the date when the images were consolidated.

This is a handy file maintenance tool, and we recommend it.