Windows beta. Renamr for Windows is complete, signed, and new to this platform. You are among the first people running it, so tell me how it goes.
Safe by Design · 100% On-Device

Rename hundreds of files.
Never lose one.

Four hundred photos named IMG_0001. Renamr stacks little rename rules (Find & Replace, Number, Date, Clean Up) and shows every name as Current → New before anything happens. Collisions are refused up front the way NTFS actually compares names, renames run in two safe phases, and Ctrl Z puts the whole batch back. One click renames them all, safely and entirely on your PC.

v1.0.0 beta · Windows 10 (1809+) & 11 · 64-bit · Installs without admin rights · No account

How it works

Drop. Stack. Preview. Apply.

Drop in your files
Drag files or a whole folder onto the window from File Explorer, or paste straight from it with Ctrl V. Turn on include-subfolders and a folder brings everything beneath it too, each file renamed in place.
Stack your rules
Find & Replace, Insert, Remove, Change Case, Number/Template, Clean Up and Extension, in any order. Every rule card shows its own live example. Save a stack as a preset and reload it in one click.
Read the preview
Every file shows Current → New with the changed characters highlighted. If two names would collide, both rows say exactly what they clash with. Apply refuses until it's resolved.
Apply, or take it back
Nothing on disk changes until you press Ctrl ↵ Apply. Renames run in two safe phases, and Ctrl Z puts every name back exactly as it was.

Features & safety

Built to never lose a file.

A batch renamer touches hundreds of files at once, so Renamr treats every batch like a database transaction, then layers on the rule pipeline that does the actual renaming.

Conflicts refused, the NTFS way
On Windows, Report.txt and report.txt are the same file name: renaming one onto the other destroys a file. Renamr compares every new name the way NTFS actually does: case-insensitively, but (unlike the Mac build's APFS-safe check) without folding Unicode normalization or ß→ss, so café in NFC and NFD, or straße.txt and STRASSE.txt, stay legally different files here. It refuses to apply while any collision exists, and never blocks a rename that's actually legal.
NTFS-safe
Windows name validation, in plain English
Reserved device names (CON, PRN, AUX, NUL, COM0-9, LPT0-9; even with an extension, NUL.txt is still the NUL device), the illegal characters < > : " / \ | ? *, control characters, and names ending in a space or a dot (Win32 silently strips them) are all flagged invalid in the preview, with the reason shown inline before anything is renamed.
Windows-specific
Locked files handled per-file
A file open in another app can't be renamed on Windows. Renamr names exactly which file is locked, in plain English, and rolls the two-phase rollback back to the original state. The batch never ends up half-renamed.
Graceful failure
Long-path safe
Renames route through \\?\-prefixed paths past the old 260-character MAX_PATH limit, whether or not your machine has the long-path registry switch enabled, so deeply nested folders just work.
No MAX_PATH
Two-phase renames
Every rename goes through a unique temporary name before landing on its final one. Swaps (a → b while b → a), chains (a → b → c), and case-only renames (FILE.txt → file.txt) that would destroy files in a naive renamer simply work.
Swaps & chains
Undo any batch
Each Apply writes an undo log to disk before it finishes. Press Ctrl Z and every name in the batch goes back exactly as it was, even after you quit and relaunch the app.
Ctrl Z
Crash-recovery journal
Before touching a single file, Renamr writes a write-ahead journal of the whole batch. If the app is force-quit (or the power goes out) mid-rename, the journal is replayed on the next launch and any half-renamed files are restored to their original names.
Power-loss proof
A stackable rule pipeline
Rules apply top to bottom, each transforming what the last one produced. Reorder them, toggle them, and every card shows a live example (IMG_0001.jpg → photo_0001.jpg) computed from your actual first file.
The headline
Find & Replace: plain or regex
Swap plain text, or bring a full regular expression with capture groups. Match-case toggle, first-match or all-matches. The preview shows exactly what your pattern grabbed before you commit.
Regex
Number with templates
Build names from tokens: {n} with start, step, and zero-padding, plus {name}, {ext}, {date} and {parent}. Numbering can restart in each folder when you're renaming a whole tree.
{n} {name} {date}
Dates from EXIF or the file
For photos, {date} reads the EXIF capture date with a small pure-Python reader (no OS imaging framework needed on Windows). For everything else, the file's created or modified date, formatted with a pattern like YYYY-MM-DD.
EXIF-aware
Clean Up messy names
Collapse runs of whitespace, turn spaces into underscores or dashes, strip accents, or keep only safe characters. Or pick Windows-safe, which removes only what Windows and USB drives actually reject and leaves accents and non-Latin scripts alone: café.txt stays café.txt.
One click
Case & extension rules
lowercase, UPPERCASE, Title Case or Sentence case for names; lowercase, normalize (jpeg → jpg) or change outright for extensions. Insert and Remove rules handle prefixes, suffixes, positions and ranges.
A preview that shows its work
The Current → New table highlights just the characters your rules actually changed, so a subtle edit (one digit, one accent) is impossible to miss. Nothing on disk changes until you press Apply.
Diff highlighting
Show in File Explorer
The thing you want most right after a rename is to look at the result. One button opens Explorer with the whole renamed batch selected.
Hand-override any single name
Select a New name and press Enter or F2 and type exactly what you want. That row is pinned and skips the rule stack until you revert it. Overrides go through the same validity and conflict checks as everything else.
Pinned rows
Whole folders, subfolders too
Drop a folder and get its files; flip on include-subfolders and get the whole tree, each file renamed in place inside its own folder. Folders themselves are never renamed.
In place
Presets for rule stacks
Built the perfect photo-import pipeline (date, parent folder, counter, clean-up)? Save the whole stack as a preset and replay it next month in one click.
100% on your PC
Renamr only ever sees the files you add, and everything happens locally: no account, no cloud, no usage analytics, nothing uploaded. The only network calls are the optional license check and update check.
Privacy
13 languages
English, Español, Français, Deutsch, Italiano, Português (Brasil), Nederlands, Polski, Русский, Türkçe, 日本語, 简体中文, 한국어. Renamr follows your Windows display language automatically, and the header's language button switches it live. Counted messages use each language's real plural rules; the rename tokens stay verbatim in every locale.
Localized
Built for everyone
Fully keyboard-driven (add with Ctrl O, apply with Ctrl ↵, undo with Ctrl Z), with Narrator labels on every rule field, live announcements for async results, Windows High Contrast support, reflow with no horizontal scrolling at 150% text scaling, and axe-audited WCAG 2.1 AA contrast in light and dark.
WCAG 2.1 AA
The rules
Find & Replace Insert Text Remove Change Case Number / Template Clean Up Extension

Beta

You're testing the first Windows build.

Renamr has been on the Mac for a while. This is the Windows port's first public build: the same rule engine and safety guarantees, rebuilt around how Windows and NTFS actually treat file names. It passes its own 266-case test suite.

What would help most

Drag & drop, for real

From File Explorer, from the desktop, from a search-results list, from a network drive. Single files, multi-select, whole folders (with and without subfolders).

Files you actually own

Your own photos, your own documents. Try the edge cases too (reserved names, trailing dots, very long paths) and tell me if a real collision slips through, or a legal rename gets blocked.

The install itself

Whether SmartScreen let you through, whether the shortcut and taskbar icon look right, whether uninstall leaves anything behind.

Anything that looks wrong

Clipped text, a scrollbar where there shouldn't be one, an odd translation, a dialog you couldn't reach with the keyboard.


Pricing

Free for you. Fair for work.

Personal use is free forever: every rule, unlimited files and folders, no key, no account, no nag screens. If Renamr earns its keep at your job, a one-time business license keeps it supported.

Personal
Free forever
For individuals and personal projects
  • Every rule, from Find & Replace to Extension
  • Unlimited files, folders and subfolders
  • Conflict detection, two-phase renames, undo
  • 100% on-device, nothing uploaded
  • No account, no nag screens
  • Free updates forever
Download, Free
Business
$5 / computer
One-time payment, no subscription
  • Everything in Personal
  • Use commercially at work
  • One-time payment, no subscription
  • Free updates forever
  • Supports solo indie development

The personal tier is the full app. Buy a business license only if you use Renamr commercially. One seat per computer, paid once, yours for life. Secure checkout via Stripe; your license key is emailed instantly.


Download & install

Get set up in about a minute.

Run the installer and Renamr lands in your own user folder: no admin password, no UAC prompt, nothing else to install.

Download Renamr for Windows, Free

Version 1.0.0 beta · Renamr-Setup.exe · about 12 MB · Free updates forever

Windows 10 (version 1809 or later) or Windows 11 · 64-bit
Everything Renamr needs is inside the installer: no Python, no runtime to chase down. It does use the Microsoft Edge WebView2 Runtime to draw its interface, which ships with Windows 11 and reaches almost every Windows 10 machine through Windows Update. On the rare PC without it, Renamr will say so on launch and Microsoft's free installer is a one-click fix.
No admin rights needed
Renamr installs per-user into %LOCALAPPDATA%\Programs\Renamr, so there's no UAC prompt and no argument with your IT department. Uninstall from Settings → Apps → Installed apps like anything else.
Windows may warn you the first time. Here's the honest story.
Renamr is Authenticode-signed, so the publisher shows as a real, verified name rather than "Unknown publisher." But signing alone does not switch SmartScreen off: Microsoft builds reputation per file, and a brand-new build starts with none. Until this exact file has been downloaded enough times, you may still see a blue "Windows protected your PC" box.
  1. Click More info
  2. Check the publisher name shown
  3. Click Run anyway
I'd rather tell you this up front than have you wonder. Never click through that box for software you don't trust the source of.

FAQ

Common questions.

Is Renamr really free?
Personal use is free forever: every rule, unlimited files and folders, no account, no trial timer, no nag screens. If you use Renamr at work, a one-time $5 business license per computer keeps it supported.
Can Renamr overwrite or lose a file?
That's the one thing it's built never to do. Before anything moves, Renamr checks every new name against every other one the way NTFS actually compares them, and refuses to apply while any collision exists. The comparison is case-insensitive but, unlike the Mac build's APFS-safe check, does not fold Unicode normalization or ß→ss, so café in NFC and NFD are still legally different files here. The renames themselves run in two phases through unique temporary names, so even swaps (a → b while b → a) and chains can't collide mid-flight.
What if I don't like the result?
Press Ctrl Z. Every Apply writes an undo log to disk first, and one undo puts every name in the batch back exactly as it was, even after you quit and relaunch.
What happens if my PC crashes mid-batch?
Each batch is protected by a write-ahead journal that's saved before any file is touched. If Renamr (or Windows itself) dies partway through, the journal is replayed on the next launch and any half-renamed files are restored to their original names.
Does Renamr upload my files anywhere?
No. Renaming happens entirely on your PC. Your files and their names are never uploaded, and there is no account and no usage analytics. The only times Renamr contacts our server are to validate a business license key or to check for updates, which sends the app version.
Can I use regular expressions?
Yes. Find & Replace and Remove both take plain text or a full regular expression, with a match-case toggle and first-match/all-matches control. The live preview shows exactly what your pattern matched before you commit to anything.
How does numbering work?
Add a Number/Template rule and build the name from tokens: {n} with start, step, and zero-padding, plus {name}, {ext}, {date} and {parent}. A template like {date} {parent} {n} turns IMG_4021.jpg into 2026-07-04 Yosemite 001.jpg. With subfolders included, numbering can restart in each folder.
Where does {date} come from?
For photos, from the EXIF DateTimeOriginal (the moment the shutter actually fired), read by a small pure-Python parser since Windows has no built-in imaging framework to ask. For everything else, or when EXIF is missing, the file's created or modified date. You choose the format with a pattern like YYYY-MM-DD.
Can I rename files inside subfolders?
Yes. Turn on include-subfolders and dropping a folder pulls in the files beneath it too. Each file is renamed in place inside its own folder, and folders themselves are never renamed.
Can I hand-edit just one name?
Select any New name and press Enter or F2 and type exactly what you want. That row is pinned and skips the rule stack until you revert it, and overrides still go through the same conflict checks, so a hand-typed collision is refused like any other.
What names does Windows reject, and does Renamr catch them?
Yes, before you ever press Apply. Reserved device names (CON, PRN, AUX, NUL, COM0-9, LPT0-9, even with an extension), the characters < > : " / \ | ? *, and names ending in a space or a dot (Win32 silently strips them, which can point two different names at the same file) are all flagged invalid in the preview, with the reason spelled out inline.
Why did Windows show a blue "protected your PC" warning?
Because the file is new, not because it's unsigned. SmartScreen builds trust per file over downloads and time, and a fresh build starts from zero. Code signing gives you a verified publisher name in the dialog but does not skip it. Click More info → check the publisher → Run anyway. See the install section for the full explanation.
How do I update Renamr?
It updates itself. Renamr quietly checks about once a week and badges the update button when there's something new (never a pop-up), and you can turn the check off. Click it and Renamr downloads the new installer, verifies its signature and version before running anything, installs over itself and reopens. If any of those checks fail it deletes the download and sends you here instead. Your presets and settings carry over.
How is this different from the Mac version?
Same rule engine, same preview, same undo and crash-journal guarantees, rebuilt around Windows APIs and NTFS rather than macOS and APFS. Two things are genuinely different: conflict detection here follows NTFS's real (non-Unicode-normalizing) comparison instead of APFS's, and this build validates Windows-only naming traps (reserved device names, illegal characters, trailing dots) that macOS simply doesn't have. Long paths route through \\?\ here too, since Windows' old 260-character limit has no Mac equivalent.
Where do my settings live, and what does uninstalling remove?
Preferences and presets sit in %APPDATA%\Renamr and your license key in your user profile. Uninstalling removes the app from %LOCALAPPDATA%\Programs\Renamr; delete those two if you want every trace gone. Nothing is written outside your user account, and nothing goes in the registry beyond the uninstall entry.