Bulk Rename Files, Fix Wrong Extensions
SmartBatchRenamer reads file contents to detect the real format instead of trusting the filename. It warns about wrong or missing extensions without blocking the task, corrects them in one click, and saves batch rename rules for reuse.
Key Feature · File Extension
Detect the Real File Type. Correct the Extension.
Most rename tools only edit text. SmartBatchRenamer also inspects each source file's contents, finds wrong or missing extensions, and makes the correction part of the batch rename workflow.
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Detect Format from File Contents
Inspect file signatures and internal structure to identify the real format. If the content is unknown, fall back safely to the source extension in lowercase instead of guessing.
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Distinguish Shared Containers
Look inside formats that use the same ZIP container and tell DOCX, XLSX, PPTX, APK, EPUB, and JAR apart instead of labeling every one as ZIP.
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Warn, Then Correct in One Click
Check every file, even when no other rule renames it. Warnings never block the task; after confirmation, the correction rule always runs after all active rename rules.
Extension correction examples
annual-report.zip annual-report.docx Content is actually a Word document
travel-photo travel-photo.jpg Missing JPEG extension detected
For truly equivalent spellings, you stay in control: choose jpg / jpeg / jpe, tif / tiff, or db / db3 / sqlite / sqlite3.
Features
A Complete, Reusable Batch Rename Workflow
File Extension Detection & Correction
Identify the real format from file contents, flag wrong or missing extensions, and correct them as part of a batch rename.
Reusable Batch Rename Rules
Create a complete rename rule from insert, replace, and delete operations plus date, incrementing sequence, and random sequence parameters. Apply the same rule again when similar tasks come up.
Live Filename Preview
Preview every new filename before applying a batch rename. Step-by-step changes make it clear exactly what each operation changes.
Rename Conflict Detection
Automatically detect duplicate names inside the batch and same-name files in the target directory before anything changes.
One-Click Undo for Renames
Undo an executed batch rename with one click and restore every file's original name when a rule needs adjustment.
Dates, Sequences, and Reusable Parameters
Add date/time values, incrementing sequence numbers, and random sequences once, then reuse them across complex filename rules.
Showcase
Product Showcase
Drag, Drop, and Rename Multiple Files
Add files by dragging them straight into the window. The file list shows original names, new names, and results, with sortable columns for large batches.
Preview Operation-by-Operation Filename Changes
As you add search-and-replace, delete, insert, numbering, or date operations to a rule, watch each filename transform step by step. Reuse the finished rule in later batches.
Dark Mode for Long Renaming Sessions
A carefully designed dark mode follows your system theme automatically, keeping long photo, document, and media file cleanup sessions comfortable.
Use Cases
Where It Shines
Rename Camera Photos
Batch rename camera photos from Canon, Nikon, Sony, and other common filename formats by date or sequence number
Rename Phone Photos
Rename iPhone and Android photo files in batches so albums follow a clean timeline
Rename Documents
Apply consistent filename rules to contracts, reports, invoices, and other document batches
Clean Media Filenames
Standardize music and video filenames in batches to keep large media libraries organized
FAQ
File Extension Detection and Batch Renaming Questions
- How does SmartBatchRenamer detect the real file format?
- SmartBatchRenamer reads signatures and internal structures from the file contents instead of trusting the filename. It can distinguish DOCX, XLSX, PPTX, APK, EPUB, and JAR even though they share a ZIP container. When content cannot be identified, it falls back to the existing extension in lowercase.
- Can it correct a wrong or missing file extension?
- Yes. Every file is checked even when no other rule changes its name. A mismatch produces a non-blocking warning; after you confirm the correction, the ExtName template rule always runs after all active rename rules.
- Can I preview filenames before applying a batch rename?
- Yes. Every rename rule updates the preview before execution, so you can compare original filenames with the new filenames first.
- Which rename operations can I use in a rule?
- SmartBatchRenamer supports insert text, search and replace, and delete-character operations. Operations can also use date/time, sequence number, and random sequence parameters, then be combined into a complete rename rule.
- Can I reuse rename rules for future tasks?
- Yes. After creating rules and saving them as template rules, you can reuse that rule set in later batch renaming tasks without rebuilding it from scratch.
- Can I undo a batch rename?
- Yes. After a rename is executed, one-click undo restores every file's original name.
- Are my files uploaded during renaming?
- No. File lists and rename operations are handled locally on your device, and file contents are not uploaded for batch renaming.
Get Started with SmartBatchRenamer
Download for free and experience the convenience of smart batch renaming