Bulk Rename Files Online Free

Bulk file renaming — also called batch renaming or mass renaming — is the process of renaming multiple files simultaneously using a set of rules. Instead of clicking each file and typing a new name one at a time, you define a pattern (like “add the prefix 2024_ to all files”) and apply it across an entire folder at once.

Modern browsers are powerful enough to perform bulk file renaming entirely client-side using the Web File API, which means no upload to any server is required. BulkRenameTool uses this technology to give you native desktop-speed renaming, completely free, directly in your browser tab.

Common use cases include: renaming exported photos from a camera (e.g., IMG_0001.jpg → client_shoot_001.jpg), standardizing web assets (e.g., converting all filenames to kebab-case), and organizing batches of scanned documents with a consistent date prefix.

Need to bulk rename JPG files? BulkRenameTool handles JPEG and JPG images natively — just drag your entire photo folder into the drop zone. Whether you have 10 or 10,000 JPG files, you can apply a prefix like a date (2024-06-01_), strip the camera's generic prefix (IMG_), and add sequential numbers with 3-digit padding — all at the same time. The live preview shows every .jpg file's new name before you download.

This is especially useful for photographers delivering galleries — turn DSC00123.JPG into 2024_Smith_Wedding_001.jpg across 600 files in under 30 seconds.

Web developers and UI/UX designers frequently need to bulk rename PNG files to web-safe filenames. Filenames with spaces, capital letters, or special characters cause broken image paths on Linux servers and in web apps. BulkRenameTool's case conversion options — including kebab-case and snake_case — instantly normalize all your .png, .svg, and .webp assets.

Example: Header Image V2 FINAL.png becomes header-image-v2-final.png across your entire design handoff ZIP in one click.

If you need to bulk rename files on Windows, you have three native options — and they all fall short. File Explorer (F2) lets you multi-select and rename, but only adds a sequential number — no prefix control, no find & replace. PowerToys PowerRename is excellent but requires downloading the 80MB+ PowerToys suite and admin rights. PowerShell scripts work but require command-line knowledge.

BulkRenameTool is the fourth option: a free, instant, browser-based batch rename tool for Windows with no installation, no admin rights, and no command line needed. Open Chrome or Edge, drag in your files, and rename them in seconds. Works on Windows 10 and Windows 11.

Read the full comparison: online batch rename tool vs desktop alternatives →

macOS Finder has a built-in batch rename feature (right-click → Rename Items), but it only supports basic text replacement and number addition — no regex, no case conversion, and no live preview. For anything more complex, Mac users traditionally needed to download a third-party app.

BulkRenameTool runs perfectly in Safari and Chrome on macOS and requires zero installation. Every advanced renaming feature — regex find & replace, full case conversion, prefix/suffix, and sequential numbering with custom padding — is available immediately. It's the fastest way to bulk rename files on Mac without any software.

The simplest and most common bulk rename task is adding a prefix or suffix to filenames. A prefix is text added to the beginning of a filename; a suffix is text added before the file extension. With BulkRenameTool, you can add both simultaneously:

• Add prefix: Type 2024_project_ → every file becomes 2024_project_report.pdf, 2024_project_invoice.pdf, etc.
• Add suffix: Type _final → every file becomes report_final.pdf, invoice_final.pdf, etc.
• Both at once: Add 2024_ as prefix and _v1 as suffix to get 2024_report_v1.pdf.

The live preview updates in real time so you can verify every filename before downloading the ZIP.

Spaces in filenames cause headaches for web servers, shell scripts, and cloud storage systems. A file named My Document Final.pdf becomes My%20Document%20Final.pdf in a URL — ugly and error-prone. To remove spaces from filenames in bulk, use Find & Replace: set Find to a space ( ), and Replace with a hyphen (-) or underscore (_). Apply across all files in one click.

Alternatively, use the kebab-case conversion to simultaneously remove spaces and lowercase all letters — the safest format for web-facing files.

Several paid desktop applications (like A-PDF Rename or various commercial batch rename utilities) charge $20–$50 for features that BulkRenameTool provides completely free. The key advantage of paid desktop tools is offline availability and deep OS integration — but for the vast majority of renaming tasks, a browser-based tool is equally capable and vastly more convenient.

BulkRenameTool covers every renaming scenario that makes up 95% of real-world use: prefix/suffix, find & replace (with regex), auto-numbering, and case conversion. All for free. All without installing anything.