The pageSize on a CustomReport controls the page dimensions of the generated PDF. Common values include "letter" (8.5 x 11 in) for US-based reports, "A4" (210 x 297 mm) for international clients, and "tabloid" or "11x17" for large-format figures. Choosing the right pageSize before designing your blocksJson layout prevents content from being cut off or excessively padded. Combined with the orientation field, pageSize defines the full page canvas your report content is laid out on.
Technical section
Data model, API, and internals — visible to developers.