Batch file renamer

Preview a safe filename mapping.

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Privacy details

Batch file renamer processes your input in this browser. Inputs and results are excluded from analytics. Recent tools save tool names, visit counts and last-visit times. Saved tools store only their names. Draft saving is optional and stays on this device; delete saved text with the draft controls. Loading text from a URL is optional and contacts that server; its URL and your IP address are visible to the server. An optional “Use in” action keeps a handoff in this tab. The next tool removes it on arrival and ignores it if more than a minute has passed.

Copy link includes the inputs you choose to share in the address. Anyone with that link can reopen them. Files and generated results are excluded. Password and key tools share settings only.

Your input

Options and local file

New filename prefix

Starting number

Extension

Open a text file on this device

Optional settings apply only to this tab.

Your result

Reset reloads the tool with its starting values and releases open files and device controls. Saved drafts stay on this device until you delete them.

Links include your inputs and settings. Anyone with the link can see them, so leave out private text. Files and generated results are left out; random draws run again.

Keyboard shortcuts

Updated 2026-09-20

Batch file renamer explained

Preview a numbered rename mapping before touching files. Enter filenames one per line, choose a prefix and starting number, and decide whether to preserve extension case. The result is an exportable mapping; no local files are renamed.

Next: JSON formatter

A worked example

With prefix file- and starting number 1, photo one.jpg becomes file-001.jpg and photo two.jpg becomes file-002.jpg in the preview.

Before you use the result

Preview only: browser text cannot rename arbitrary files on your computer. Paths and Windows-reserved filename characters are rejected. Review the mapping and keep a backup before applying it elsewhere.

Cite this page

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ToolOctopus. “Batch file renamer.” Updated 2026-09-20. https://tooloctopus.com/batch-file-renamer.

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