Here is what Squarespace’s support docs say about page, section, and block limits, for your convenience. Be sure to reference their help documentation for the latest and most up-to-date numbers.
Reference
Squarespace Content Limits, May 2, 2024
Auto layouts - No official limit, but we recommend no more than 250 items, as pages with too much content may load and save slowly
Blog pages - No limit for the number of blog posts you can add to a blog page
Events pages - Up to 350 events per month
Fluid Engine sections - Up to 1000 grid rows
Dropdowns - No official limit, but we recommend a maximum of 10 pages to keep drop-down menus manageable
Gallery sections - Up to 250 images
Layout pages - We recommend adding no more than 60 blocks per page, as pages with too many blocks may load and save slowly
Page sections - No official limit, but we recommend adding no more than 20 sections per page, as pages with too much content may load and save slowly
Portfolio pages - Up to 60 sub-pages
Portfolio sub-pages - We recommend adding no more than 60 blocks per sub-page, as sub-pages with too many blocks may load and save slowly
Store pages - Can't exceed the site-wide limit of 10,000 products
Videos pages - Up to 10,000 videos, but the video limits and requirements apply
