How do I change the page/paper size in a manuscript? (Not a new document)

I have a two hundred—plus page document in letter format, and need to change it to 6"x9" format, but have not found a way to do that for more than a single page at a time.

I did a “select all” but the Format>page options remained disabled.

Surprisingly, I have not found an answer to this simple thing.

How do I change the >document’s< pages to this new size, all at once? All two hundred pages, from letter size to 6"x9".

You may only change page settings for one (current) section (from one page-break-with-page-style to another). See this question.

Your document seems to either have multiple such sections, or you apply a page style with its “Next style” set to something else. In first case, if you need the same page style for all pages in your document, you only need to select all document and in Format-Paragraph-Text Flow uncheck “With page style:” (make sure it’s cleared, not checked or grayed). In second case, you need to modify required page style to have “Next style” set to itself (see Styles and Formatting sidebar, Page Styles-select required style-right click-Modify...-Organizer-Next style).

In LO, page size and other stationery parameters are defined in so-called Page styles.

Even with 200+ pages, your document should not be built on more than a handful of page styles. To see them, open Format>Styles & formatting or F11. Select the fourth icon from the left in the tool bar and Applied styles from the drop-down menu at the bottom. The list will then show only the styles used in the document.

The parameters for the remaining page styles may be adjusted by right-clicking on the name and choosing Modify....

Don’t forget to change also the paper size in the printer settings, which are independent from the page styles.

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In this is in Styles > Styles & formatting, not Format > ..

@EasyTrieve: Thanks for the update, I’m still on an older version on my stable “production” computer.

Yes. This is my first book edit using LO Writer/ODT (5). The first page is “styled” as “First Page”, followed by a section page styled “Index,” followed by the rest of the book page styled “Default.”

This allowed me to set pre-content page numbering to lower case Roman numbers, and reset story numbers to Arabic, starting at page 1.

These styles are separated by inserting “Manual Page Break(s)”, which allows you to set the page style to a different style, or the same style.

So I’ve learned that paper format is nested inside of page styles, rather than being a global value set outside the manuscript. Huh. I need to learn more about open document format(s).

Now that I’ve seen how this works, it does not seem so hard to do.

Thank you for your help.