How to rotate pages in a PDF so they stay rotated

Half the pages of your scanned document are on their side. You click rotate, everything looks right and you close it, but the next time you open the file the pages are sideways again.

It isn't a bug. It is the most common mix-up with PDF rotation.

Two different rotations

Viewing rotation turns the page on your screen. Like the zoom level, it only lasts while the file is open. Nothing in the file changes, and closing the document forgets it. This is what the rotate button in most readers does.

Document rotation is saved inside the PDF. Each page stores an angle of 0, 90, 180 or 270 degrees. Change that and save, and the page opens rotated for everyone, everywhere, from then on.

Most viewers offer the first and only some offer the second, which is why "I rotated it and it didn't save" happens so often. In Adobe Reader the rotate button under View only changes the view. The one that saves is in Acrobat Pro's page tools.

Making it stick

Rotate PDF saves the rotation into the file. Choose the pages and the direction, save, and the document stays rotated in every reader, when printed, and when someone else opens it.

Rotation is lossless. The page content isn't redrawn. Only the stored angle changes. There is no quality loss, however many times you rotate.

Why scans come out sideways

The usual causes, roughly from most to least common:

The feeder. Sheets fed in landscape are captured landscape, whatever is printed on them. Mixed batches, like a portrait report with a landscape spreadsheet stapled in, come out mixed.

Auto-rotate guessing wrong. Many scanners try to work out the direction from the text. On a page that is mostly a table, a form or a diagram with few words, it guesses, and it guesses wrong often enough to be annoying.

Phone photos. Cameras often save the direction as a note in the photo instead of turning the image itself. Some programs follow the note and some ignore it, so the same photo looks upright in one program and sideways in another. Once it is inside a PDF, that stays unclear.

Rotating some pages and not others

This is the usual case. A bundle normally has a few sideways pages among many correct ones.

Two things make it quick:

• Work from thumbnails, so you can see which pages need turning rather than opening each one.
• Note the direction. 90 clockwise and 90 anticlockwise both fix a sideways page, but only one puts the text the right way up. Pick the wrong one and the page ends up upside down instead of on its side.

For a page that is fully upside down, 180 degrees works in either direction.

Rotation and page numbers

This catches people out. If you rotate pages and then add page numbers, the number should go on the page as it is shown, so bottom right means bottom right as the reader sees it.

If a tool ignores rotation, a 90-degree page gets its number along the side, turned. If some pages in a mixed document have numbers in odd places, that is the cause.

The safe order is to rotate first, then number.

When rotating is not the fix

If your scan is slightly crooked instead of a clean 90 degrees off (three or four degrees, as happens when a page goes through at an angle), rotating won't help. You need straightening, which most scanner software offers. It straightens the content instead of turning the page in quarter-turns.

A crooked page also makes OCR much less accurate, so fix it before running text recognition. Enhance PDF can clean up a poor scan, but if you still have the paper, the best fix is to scan it again with straightening turned on.

Checking before you send

Open the finished file in a different program from the one you edited it in. A browser works well, because it can't remember what you did in the other program. If the pages are upright there, the rotation is saved in the file.

Why the rotation you did in your viewer disappeared

Nearly every PDF reader has a rotate button, and it almost never saves.

That is on purpose. The viewer's rotate button only changes the display. It turns the page on your screen so you can read it, until you close the file. Nothing in the file changes, so the next person to open it sees it sideways again, and so do you tomorrow.

The rotation that lasts is saved into each page of the document. Every viewer reads it and every printer follows it, because it is part of the file and not part of one person's screen.

If you ever rotated a page, sent the file, and were told it is still sideways, this is why.

Which direction, in plain terms

The wording confuses people because "rotate left" can mean rotating the page or rotating your head.

The useful test: look at where the top of the text is now.

• Text runs bottom-to-top with the top of the letters on the left: rotate 90° right.
• Text runs top-to-bottom with the top of the letters on the right: rotate 90° left.
• Text is upside down: 180°, and direction doesn't matter.

If you get it wrong, rotating back by the same amount puts it back exactly. Rotation is lossless, so a wrong turn does no harm.

Mixed orientation in one document

A scan of a report with a landscape table in the middle usually arrives with everything portrait and the table sideways.

Rotate only those pages, not the whole document. You get a PDF where most pages are portrait and a few are landscape. That is normal and prints correctly, because printers read the rotation of each page.

The mistake to avoid is rotating everything so the table reads properly, which fixes one page and breaks forty.