PDF tools: crop, split, rotate, merge, and spreads

Prepare PDFs for OCR with LEXO's local PDF tools. Extract page ranges, split, crop margins, rotate, merge, and split two-up spreads, in the app or the CLI.

LEXO’s PDF tools run entirely on your computer. They need no Google account and no network. Use them to clean up a document before OCR, or on their own.

Every tool is available in the desktop app (the Edit, Pages, and PDF tabs) and as a lexo pdf command.

Page ranges

Commands that take --pages (-p) accept:

all, odd, or even;
single pages and ranges, comma-separated: 1-3,7,10-. An open range like 10- runs to the last page.

Pages are numbered from 1.

Inspect a PDF

lexo pdf info book.pdf

Prints the page count, whether the PDF has a text layer, and the size of page 1.

Extract a page range

lexo pdf extract book.pdf --pages "1-3,7,10-" -o subset.pdf

In the app: select thumbnails, then Extract selected to new file….

Split into several files

By chunk size:

lexo pdf split book.pdf --every 10

Or at specific pages, each of which starts a new file:

lexo pdf split book.pdf --at 4,7

Output goes next to the source unless you pass --out-dir.

Crop margins

Percentages trimmed from each edge:

lexo pdf crop book.pdf --top 8 --bottom 8 -o trimmed.pdf
lexo pdf crop book.pdf --left 5 --right 5 --pages odd -o trimmed.pdf

In the app, the Edit tab’s crop box does the same visually, and you can apply it to one page, all pages, or a selection. Cropping rotated pages trims the edge you see in the preview.

Rotate

lexo pdf rotate book.pdf --degrees 90 -o rotated.pdf
lexo pdf rotate book.pdf -d 180 --pages even -o rotated.pdf

--degrees takes any multiple of 90.

Merge

lexo pdf merge front.pdf body.pdf back.pdf -o book.pdf

Files are joined in the order given. In the app, Append PDF(s)… in the PDF tab adds files to the end of the open document.

Split two-up spreads

Scans of open books often hold two pages per image. Split each into left and right halves:

lexo pdf split-spread scans.pdf -o pages.pdf

--ratio moves the cut if the gutter isn’t centred, from 0.05 to 0.95 (default 0.5):

lexo pdf split-spread scans.pdf --ratio 0.52 -o pages.pdf

In the app, Show split line lets you drag the cut onto the gutter, then Split two-up at line.

After splitting, each spread becomes two single pages in the pages strip. — After a split: each spread is now two pages, left half first.

Splitting respects page rotation and the current crop, so re-splitting an already-split PDF doesn’t duplicate halves.