Batch Rename

Select several files, right-click, and choose Batch Rename…. The sheet shows a live preview of every name before and after, and nothing touches the disk until you press Rename.

Three steps, applied in order

The sheet has three numbered steps, and they all run in a single pass, top to bottom:

  1. Find & Replace — swap text inside the name, literally or by regular expression
  2. Prefix & Suffix — add text before and after
  3. Number — append or prepend a sequence number

Leave a step blank and it does nothing, so using just one of them works exactly as you'd expect. Fill in several and they compose:

Find IMG_, replace Holiday
Prefix 2026_, suffix _final
Number on, start 1, pad 3, separator _
ResultIMG_01.jpg2026_Holiday01_final_001.jpg

The order is fixed, and chosen because it's nearly always the one you want: replacing first means your search matches the original name rather than a prefix you just added, and numbering last keeps the counter clear of the other steps.

Find & Replace

Type text in Find and it's replaced wherever it appears in the name. Leave Replace empty to delete the matched text instead. Case sensitive is on by default.

Turn on Regular expression for pattern matching. In the replacement, $1, $2… insert the capture groups from your pattern:

FindReplaceIMG_01.jpg becomes
^IMG_(\d+)$shot-$1shot-01.jpg
\s+_(spaces collapse to underscores)
[^a-zA-Z0-9._-](empty)(strips anything not alphanumeric)
(\d+)#$1IMG_#01.jpg

While a pattern is incomplete or invalid, Iruka shows the reason under the field and Rename stays disabled — otherwise the broken step would quietly match nothing and you'd apply only the other steps without noticing.

Prefix & Suffix

Prefix goes at the front of the name. Suffix goes at the end of the name but before the extension, so a suffix of _final turns report.pdf into report_final.pdf, not report.pdf_final.

Number

Switch on Add a sequence number, then choose:

  • Position — before the name (Prefix) or after it (Suffix)
  • Start — the first number in the sequence
  • Pad — how many digits, zero-filled, so 3 gives 001, 002, 003
  • Separator — the character between the number and the name

Files are numbered in the order they appear in the file list, so sort the folder the way you want them numbered before opening the sheet.

Extensions are never touched

Every step works on the name only. archive.tar.gz keeps its .gz, and a file with no extension at all is renamed cleanly without one being invented.

Preview and undo

The preview lists every selected file with its new name; changed rows are highlighted and the header counts how many will actually change. If nothing would change, Rename is disabled.

A batch rename is a single undo step — one ⌘ Z puts every name back, and ⇧ ⌘ Z redoes the whole batch.

Limits

One find/replace per pass, in the fixed order above. If you need two different replacements, or want the replacement to see a prefix you just added, run the sheet twice.