When comparing FlashRenamer vs Flexible Renamer, the Slant community recommends FlashRenamer for most people. In the question“What are the best bulk rename tools for Windows?” FlashRenamer is ranked 8th while Flexible Renamer is ranked 9th.
Ranked in these QuestionsQuestion Ranking
Pro All-in-one batch file rename utility
Pro Easy to use functions
Pro Complete set of music features
Supports mp3, ogg vorbis, wma, mp4, flac, mpc, spx, tta, wv and more. You can also write tags based on filename.
Pro Search and replace within filenames
Pro Power users' functions
You can create your own rename rules with scripting, rename according to CSV lists, rearrange parts of the filenames, edit filenames in the text editor, extract media properties & metadata, such as width/height and duration. It is also possible to extend FlashRenamer with ExifTool for thousands of more properties and tags.
Pro Realtime preview shows changes before you actually rename
Pro Unlimited undo
Pro Fast and customizable
You can right-click context menus to quickly access FR when you need it, and save your favorite commands as presets.
Pro Powerful but easy to use
It has many options, including renaming using tags (ID3, Exif...), can number files, use wildcards or regular expressions, walk a hierarchy of folders.
And it has presets for common renaming tasks, like removing parentheses, "Copy (n)" or "Shortcut of", and so on. Its preview feature avoids errors, and warns (a bit late though) of naming conflicts.
Freeware and lightweight (archive is less than 2 MB).
No install, but might need removing options of Explorer integration / scripting if removing.
Pro Context menu in Explorer
Can add a context menu to Windows Explorer to rename files in a chosen folder.
Pro Tag management
Can rename using ID3 (music), Exif (photo), IPTC (images), DOC or HTML tags.
Pro Has many translations
Available in English, Japanese, French, Spanish and German.
You can write scripts in VBScript or in JScript (native Windows scripting languages) for complex renaming operations.
Con Development ended in March 2016 (v.6.8)
Con Seems to be no longer maintained
Last updated in 2011 (v. 8.4). Yet it works fine in Windows 10 and still does a tremendous job.