Reply To: Converting book trim formats

You can change it in InDesign, but you will have to tweak your gutters and margins a bit.

Just go to document setup and change your size, and be sure you have the layout adjustment options checked (it’s under liquid layout). Then you will need to compensate by adjusting your gutters and margins so the column measure remains the same. And the top and bottom margins.

I’m always working on books where they change trim sizes.

Another option, if you have PitStop, is to remove the cropmarks of your PDF, and put in new ones at your new trim size. Though that will depend if the printer has no problem with that.