Is there a simple way to replace all spaces in file names with _ in the book browser?

jwes · 01-09-2026, 05:48 PM

The best I've come up with is to have the strings below in a text editor and then copy and paste them each time into regex rename.
(.*) (.*) (.*)
\1_\2_\3
(.*) (.*)
\1_\2

KevinH · 01-09-2026, 06:03 PM

What generates the spaces into file names? I rarely if ever encounter spaces anymore in files names inside epubs.

Assuming this is a common problem, you can use a file base name and automagically number files in BookBrowser around that base which I commonly use for Chapters leaving only front matter and end matter to hand edit the names for but that changes the root name of the file.

Using Regex Rename is probably the easiest way to preserve parts of existing file names.

Have you tried using (\s) at the Regular Expression and _ as the Replacement?

Seems to work for me.

jugaor · 01-09-2026, 06:28 PM

Indeed.
But you don't need to capture the search.
And better with “+”, just in case:

Code:

\s+
_

KevinH · 01-09-2026, 07:19 PM

Quote:

Originally Posted by jugaor

Indeed.
But you don't need to capture the search.
And better with “+”, just in case:

Code:

\s+
_

Yes, that is simpler and better.

jwes · 01-10-2026, 02:55 AM

Quote:

Originally Posted by jugaor

Indeed.
But you don't need to capture the search.
And better with “+”, just in case:

Code:

\s+
_

Thank you. I looked at the example in the manual and made the wrong assumption that I needed to recreate the entire new file name. This might be another good example if someone wants to add it to the manual.

jwes · 01-10-2026, 03:27 AM

Quote:

Originally Posted by jwes

Thank you. I looked at the example in the manual and made the wrong assumption that I needed to recreate the entire new file name. This might be another good example if someone wants to add it to the manual.

Here are some pictures that could be used.

KevinH · 01-10-2026, 10:42 AM

You probably do not want single or double quotes inside a file name either. Starting a file name with a real alpha character instead of punctuation or a digit is also highly recommended.

So you should expand that regex to handle those replacements as well.

01-09-2026, 05:48 PM	#1
jwes Connoisseur Posts: 95 Karma: 10 Join Date: Jul 2023 Device: none	Is there a simple way to replace all spaces in file names with _ in the book browser? The best I've come up with is to have the strings below in a text editor and then copy and paste them each time into regex rename. (.) (.) (.) \1_\2_\3 (.) (.*) \1_\2

01-09-2026, 06:03 PM	#2
KevinH Sigil Developer Posts: 9,208 Karma: 6565382 Join Date: Nov 2009 Device: many	What generates the spaces into file names? I rarely if ever encounter spaces anymore in files names inside epubs. Assuming this is a common problem, you can use a file base name and automagically number files in BookBrowser around that base which I commonly use for Chapters leaving only front matter and end matter to hand edit the names for but that changes the root name of the file. Using Regex Rename is probably the easiest way to preserve parts of existing file names. Have you tried using (\s) at the Regular Expression and _ as the Replacement? Seems to work for me. Attached Thumbnails Last edited by KevinH; 01-09-2026 at 06:17 PM.

01-09-2026, 06:28 PM	#3
jugaor Enthusiast Posts: 39 Karma: 10 Join Date: Jun 2011 Location: Lima, Peru Device: Kindle 10Gen / Kobo Aura HD / Nook STR	Indeed. But you don't need to capture the search. And better with “+”, just in case: Code: \s+ _

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01-10-2026, 10:42 AM	#7
KevinH Sigil Developer Posts: 9,208 Karma: 6565382 Join Date: Nov 2009 Device: many	You probably do not want single or double quotes inside a file name either. Starting a file name with a real alpha character instead of punctuation or a digit is also highly recommended. So you should expand that regex to handle those replacements as well.