1-4a Rename. The best batch file renamer around

1-4a rename

Excellent freeware file renamer for large file numbers.
One For All






Instant preview (optional)

I hate it, if I have to rename 200 files and I don't know what the result will be.

With 1-4a rename you'll get the before/after view. Side by side.

You can turn Instant preview off for faster display.

Expert Mode and Basic Mode

Toggle between 2 modes. Basic mode for standard renaming options like replacing letters within filenames, inserting letters or numbering (pic1.jpg, pic2.jpg...). Expert mode features the full power of 1-4a rename.

Files are marked

All files that would change their filenames are marked automatically by a "X". So you see immediately which files stay the same and which would be renamed.

Additionally: If a file only changes its case ("HALLO.JPG" => "hallo.jpg") it is marked by a "x" instead of an "X".


All functions are available immediately. No sub-menus, sub-sub-menus or tabs.

Additionally descriptions pop-up as soon as you point your mouse over the functions.

Colorful display

Groups of similar functions differ in color. Functions which are disabled differ in color also.

Choose your font

Toggle between 2 fonts (fixed width and proportional width). Or choose your own font (press ctrl-font).

Change view mode

By default 3 parts of the files are visible: "Original filename", "Resulting filename" and "Path". If filenames are too long, you would have to scroll. But 1-4a allows you to toggle between Show only original filename and Show only resulting filename.

Additionally the columns are fully resizable. Set back to default widths by pressing "Reset".

Freely resizable

Small resolutions  like 640x480 (see screen capture) work, and 1600x1200 also (see screen capture) (The bigger the better :-)

The display will adapt fluently to the window size, leaving you with the biggest file pane possible.

Additionally you can maximize and unmaximize the display, so that no functions are visible, just the file names.

Additionally you can minimize and unminimize some function panels for more space.

Some basic functions #1


All Important Renaming Functions
immediately at your fingertips


Insert a any text at any position or replace any text by any text. Insert any text even before the filename (e.g. position "-13"), at the end (position "0") or even after the filename (e.g. position "129").

Example: Replace "a" to "o" ("Ammamo" => "Ommomo").
Example: Swap "a" and "o" ("Ammamo" => "Ommoma").

  • Overlay instead of insert (optional)
  • Replace case sensitive. So "a" would be replaced, but not "A"
  • Keep case (optional)
  • Replace only 1 time (optional)
  • Trim spaces to the left and right (optional): So Replace "at" by "@" in "Masters at work" would result in "[email protected]" instead of "Masters @ work"
  • Replace not the first occurence, but the second occurence, the third...the last (optional)
  • Replace matching part or the whole filename/extension.
  • Replace while filename by its 4DOS descript.ion file description. Extremely useful, if you have short DOS filenames (8+3), but have a descript.ion file available with long descriptions inside.

Process only Name/Only extension/Whole name

You define which part of the filename should be processed.
Just one click: Only the name.
Just one click: Only the extension.
Just one click: Both.

What divides name from extension? Is it always a dot "." ?

No! YOU define it.

This is extremely useful if you want to process only a part of the filename.
For example you have "Michael Jackson - Thriller.mp3". Now you want to UPPERCASE only "Michael Jackson".
Just define " - " as the name/extension separator and only process the name.

Additionally you can specify not a character (".") but a position. So 1-4a rename can treat chars 1 to 6 as the name and 7 to the end as the extension. You may use minus values also. "-3" would define the last 3 letters as extension.

Additionally you can use "?". So "?.?" as a separator in the filename "Jackson.mp3" would result in "Jackso" as the name and "p3" as the extension and "n.m" as the separator. This is useful if you want change the filename up to 1 char before the extension, 2 chars before it etc.

Changing case
  • Everything to UPPERCASE: "MammA.jpg" => "MAMMA.JPG".
  • Everything to lowercase: "MammA.jpg" => "mamma.jpg".
  • Everything to switched: "MammA.jpg" => "mAMMa.JPG".
  • Every First Letter Of Each Word (English syle): "mammA and pAppa.jpg" => "MammA And PAppa.jpg".

The following is different to other renamers:
With other renamers you have an option like "Change the first letter to uppercase".

But what they do is to make everything lowercase and the first letter uppercase.
But what if you want to keep every case (instead of changing it to lowercase)?

No problem with 1-4a rename:
First to LeaveCase then FirstLetter: "mammA.jpg" => "MammA.jpg".

Intelligent Casing (optional)
"Paul Mccartney - You and i" => "Paul McCartney - You and I".

Insert functions

Don't insert/replace a defined text, but a text depending upon the filename itself:


  • <n3-5> Insert only letter 3-5 of the filename
  • <dDDD, ddcc of MMM yyyy> Insert date: "Mon, 31st of Nov 1997"
  • <s> Insert size (decimal, hexadecimal, Latin...)
  • <f> Insert folder name
  • <p> Insert full path
  • <e2-1> Insert extension letters 1-2, but in reverse order.
  • <##> Insert file number of the sorted files
  • <#o> Insert file number of the unsorted files (Original file number)
  • <#t> Insert total files number
  • <#r> Insert random number (no duplicate numbers will be generated)
  • <l> Insert length of filename (without extension)
  • <Dddcc of MMM yyyy> Insert today's date: "23rd of Dec 2001"
  • <dxxxxxxx> inserts STAR TREK stardate (type 1) and
    <dXXXXXXX> inserts STAR TREK stardate (type 2). See also examples.
  • <i> Insert separator
  • <4> Insert description, as read from the descript.ion file.
  • <thh> Insert file hour
    <tii> Insert file minute
    <tss> Insert file second
    <thhp> or <thhpp> Inserts hour the English way ("1pm").
    <t.fff> insert the time as a fraction of a day, so 12:00 noon would be ".5"
    You can use this to insert STAR TREK startime
  • <c&> Insert spaces (or whatever is defined in field "fill up with") of the length needed to make all files the same length (see examples).
  • <cu> Inserts random uppercase char
    <cl> inserts random lowercase char
    <c#> inserts random number char
    You can combine c,l,u so <cul> would insert a lowercase OR an uppercase char. <cl#> would insert a lowercase or a number. <clllu> would insert three times more likely a lowercase char than an uppercase char.

Additionally you can add a "&" to add a leading zero to justify the output. So <s> would result in "133" (if the file size is 133 bytes), but <s&> would result in "0133" if the biggest file size is a 4digits file size (like 1035).

Note: Insert function which insert letters (like <n>, <e>, <p>) may be inserted as lowercase or uppercase by adding an"u" or a "l". So <nu1-3> would insert the first 3 letters of the filename as uppercase letters.

Note: Insert functions <n>, <e>, <4>, <i> work also with negative numbers, meaning that you can insert the xxx LAST letters of a file's name, extension, separator, 4DOS description. See Examples

  • Want to number files
    No problem (see examples)
  • Want to REnumber files:
    holiday12.jpg => holiday1.jpg
    holiday15.jpg => holiday2.jpg
    holiday32.jpg => holiday3.jpg

    No problem (see examples)
  • Want to add a leading zero (or a leading space) without changing the number itself?
    file1.jpg => file001.jpg
    file17.jpg => file017.jpg

    No problem (see examples)
  • Want to add a value to an existing number? For example increase all existing numbers by 3?
    file1.jpg => file4.jpg
    file17.jpg => file21.jpg
    No problem. How about multiply by 134? No problem.
  • Want to renumber them not to the decimal system, but to hexadecimal, octal, binary, excel (A,B,C..AA,AB), Roman/Latin (I, II, III...), IP (xxx.xxx.xxx.xxx) or whatever system? No problem.
  • Big numbers like 432498732549827354453245? No problem.
  • Insert a number separator for large numbers (8432532 => 8'432'532). No problem.
  • Renumbering start from 1 for each new folder? No problem.

Renumbering example
Insert filesize as Latin number before filename





Special functions for music/mp3 files

Often needed functions, especially for music files (optional)
  • Delete beginning number, if filename starts with a number.
    "12- Michael Jackson - Thriller.mp3" => "Michael Jackson - Thriller.mp3" (typical when grabbing or converting)
  • Replace underscore "_" if possible: "don_t" => "don't", "i_m" => "i'm" etc.
  • Replace underscore "_" to space between letters: "Michael_Jackson" => "Michael Jackson". Typical when downloading files from the internet.
  • Delete unnecessary space: "He & You" => "He&You", "( Remix )" => "(Remix)" etc
  • Typical song renamings: "Featuring" => "~", etc
  • Delete space at the beginning and at the end. Kill double space.

Shorten filenames for CD-Rs

If you write CDs they can only can contain filenames with 64 chars or less. Thus 1-4a rename can try to

  1. Shorten the filename: deleting unnecessary spaces (additional to the above mentioned function)
  2. Destruct the filename "Remix" => "Rmx" etc.
  3. Delete space between letters and make letters uppercase: "Michael Jackson-Beat it.mp3" => "MichaelJackson-BeatIt.mp3"
  4. Delete Vowels "Stevie Wonder - Happy birthday" => "Stv Wndr - Hppy brthdy"
  5. Delete double letters: "Madonna" =>"Madona"

You will see the changes immediately plus the number of letters above 64.

Additionally you can choose to not accept changes, if the filename is still too long.

See examples how it works.

Deletes/Replaces typical music parts (optional)
  • Delete beginning "The": 'The Doors - " "Doors - "
  • Replaces "and the", "and" by "&"
  • Replaces "featuring", "ft.", "feat." by "~"
  • Replaces "versus", "vs." by "^"
  • Replaces "meets" by ""
  • Deletes appended "_wav" (typical for Winamp)
  • Deletes appended "_mp3" (typical for Winamp)
  • Replaces "%20" by space
  • Deletes numbers at the beginning of the filename (typical for Winamp): "1- Michael Jackson - Thriller" => "Michael Jackson - Thriller".
  • Deletes unnnecessary space: " ( " => "(", "John' s" => "John's".
  • Delete double space, space at the beginning and at the end of the filename: " Michael  Jackson - Thriller " => "Michael Jackson - Thriller".

Swap parts within filename

This typically needed with music filenames:
"Thriller - Michael Jackson" => "Michael Jackson - Thriller"

But also with any other file type: "Pic01.jpg" => "01Pic.jpg"

See examples

Some basic functions #2



Super Sort

Extremely fast sorting

First of all, the sorting it is extremely fast. (Faster than enhanced quicksort). On my AMD650 it sorts 130'000 files by size within 5 seconds.

Sorts by value, not by ASCII char (optional)

All progs I know sort like this:


OH-MY-GOD. No human in the world would sort like that. 1-4a rename sorts value sensitive:


When is that important? If you have numbered files and you want to renumber them, you want them in the correct order before renumbering.

If you like, you can turn that function off and sort like other progs.

Sort by name, THEN sort by extension

You can sort with different levels, that means you can combine sort: If you're sorting by extension (.exe, .jpg...) what happens if there are 2 files with the same extension? You define it:

"e" sorts by extension.
"ed" would sort by date, if two files have same extension.
"eds" would sort by size, if same date, and so on.

Enhanced sort options

"n" sort by name
"e" by extension (remember: you can define what the extension is)
"u" or "" unsorted (often missing in other programs)
"l" sort by file length of the fileNAME
"L" sort by file length of the fileEXTENSION
"k" sort by length of filename (name+extension)
"K" sort by length of separator
"z" sort by zodiac (capricorn-saggitarius)
"D" sort by day of the week (monday-sunday)
"t" time, but not date
"d" by date
"s" by filesize
"p" by path (two modes fast/slow)
"r" random
"m" by reversed filename
"b" by reversed extension
"$" by first number in name (b60.txt would be sorted before a400.txt)
"#" by first number in extension
"s" by separator between name and extension

"N", "E", "P", "S" sort by case sensitive name, extension, path, separator

Sort files, which will be renamed, to top (optional)

Show all the files, which will be renamed at the top. So you don't have to scroll.

Value sensitive sorting on/off (Animated GIF)



Error Proof (Instant Problems Checking)


You've renamed 189 files. But WRONGLY!

Just press the undo button.

No identical files allowed

You are not able to start renaming, if there are two or more files, which would result in an identical file name. These files are marked by a "!"

No deleting without warning

You are warned if renaming a file would result in deleting another one. These files are marked by a "D" and the start button changes from "Start" to "Start and delete".

No illegal filenames

You are not able to start the renaming, if a filename is illegal. These files are marked by a "0".

Check whether filename would be illegal in other operating systems

You have to copy files for DOS or Macintosh. You have to make files ISO 9660 compliant? Define what is legal and illegal.

What you see is what you get

1-4a rename renames only the filenames you see marked by an "X"/"x" and renames them only to the name you see in the preview.

Skip problematic files (optional)

There is an option (Don't rename problematic files) with which you may still start renaming though there are critical files. With critical files I mean illegal filenames etc. So just skip them.

You can turn off Instant problem checking for faster display, but for safety resons you must turn it on for final renaming.

Examples of error/problem handling



Special functions

Scrambling the filename
  • Rotate the filename's letters: "look.jpg" => "kloo.jpg" (Shift function)
  • Increase/Decrease letters "ibm.exe" => "hal.exe" (Tacho function)

Change %hexvalue to letter, and vice versa

"Michael%20Jackson" => "Michael Jackson"

Eleet and uneleet

This is pretty unuseful, but much fun. Replace some letters by similar looking numbers.

1 represents l
represents z
represents e
represents a
represents s
represents b
represents t
represents x
represents g
represents o

So "eleet" would spell "31337". Weird but c001.

Some basic functions #3


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