Overview

Bulk Renamer is a free, open-source desktop app for batch-renaming files in a selected folder. It suits people who need flexible filename changes without a paid plan, especially when their files are already grouped in one folder. Its live preview and conflict checks make it a considered choice for routine batches, but it cannot reach into subfolders.

Key features

Rename patterns can combine find-and-replace, prefixes or suffixes, sequential numbering, case conversion, and extension changes. Find-and-replace supports both plain text and regular expressions, giving users room to handle consistent naming schemes as well as more targeted transformations. A live preview shows each proposed filename before changes are applied, which helps catch an unwanted pattern before it affects a batch.

Before proceeding, Bulk Renamer checks whether destination names duplicate one another or already exist on disk. A conflict stops the batch rather than allowing potentially colliding names through. That safeguard is useful when renaming important files, though it also means conflicts must be resolved before any part of the batch can go ahead.

The app works only with files in the selected folder; subfolders are excluded. Undo reverses the most recent successful batch, but the undo record is held in memory and disappears when the app closes. This is adequate for correcting an immediate mistake, not for revisiting an earlier batch later.

Pricing

Free — 0.00 USD per free. The plan requires no account and has no trial or watermark; the app is open-source under the MIT license. There is no paid tier to unlock a broader feature set, so the folder-only scope and session-bound undo apply to the free app as well. It fits users who want a no-cost desktop renamer and can work within those limits.

Platforms

Bulk Renamer runs on Linux, macOS, and Windows. The maker says unsigned apps may trigger standard Gatekeeper or SmartScreen warnings on first launch until code-signing is set up, so users may encounter an operating-system warning during installation or launch.

Who it's for

This is a sensible fit for people who create, validate, publish, or teach media and need to rename groups of files within a single folder. Its mix of text replacement, numbering, case conversion, and extension changes covers varied batch patterns without requiring payment. Choose something else if the job depends on processing subfolders or retaining undo history after closing the app.

Pros and cons

Pros: A live filename preview and checks for duplicate or existing destination names help users review a batch before it proceeds.
Pros: Regex support and several combinable rename operations suit more than simple prefix or suffix changes.
Pros: The free MIT-licensed app requires no account and runs on Linux, macOS, and Windows.
Cons: It excludes subfolders, making it a poor fit for renaming a nested directory tree in one pass.
Cons: Undo covers only the latest successful batch and is lost when the app closes.
Cons: Unsigned builds may prompt Gatekeeper or SmartScreen warnings on first launch.

Alternatives

File Renaming Software is the broader category page for comparing options. Consider Renamer.ai if a 25-renames-per-month free allowance and its Magic Folders are a better fit; its Starter plan also includes a Windows and Mac desktop app, batch renaming, and normal support.

reNamerX, Filera, Nomina, and PBRenamer are other free options for readers comparing desktop renamers across Linux, macOS, and Windows. Advanced Renamer may suit macOS or Windows users who want a free allowance capped at 10,000 files and five methods per batch, with a Personal plan offering unlimited files and methods at custom pricing. Ant Renamer is a free Windows-only option. Bulk Rename Utility is another Windows option, with separate home/academic and commercial plans.

Verdict

Choose Bulk Renamer for free, cross-platform batch renaming when your files fit in one folder and you want to preview changes and block filename conflicts before they proceed. Its flexible patterns and MIT license make it a strong match for that focused job. Look elsewhere if you need subfolder coverage or undo that survives closing the app.

	Bulk Renamer	Bulker
Free plan	Yes	No
Free trial	No	No
Paid from	Free	—
Open source	No	No
Platforms	Linux, macOS, Windows	Linux, macOS, Windows
Free plan	Yes	Yes
Platform coverage	multi_platform	—
Regex renaming	Yes	Yes
Rename preview	Yes	No
Folder renaming	No	No
Undo changes	Yes	No
Metadata-based renaming	—	No

Bulk Renamer vs Bulker

Bulk Renamer

Bulker