To ensure that your publications will run perfectly on issuu we have set a maximum upload size of:
100 MB per document for free publishers,
250MB for publishers per document on the Plus plan, and
500MB per document for publishers on the Premium plan.
If your PDF exceeds this limit, you could try reducing the file size using the instructions below.
To compress your PDFs, you can use your normal PDF software (e.g. Acrobat, Scribus, or Quark) to minimize the number of fonts, bitmapped images, and (possibly) substitute vector based-graphics with bitmap. Furthermore, consider minimizing the number and complexity of forms in your PDF document and flatten layers.
Here's a quick how -to guide on reducing file size by flattening layers in Adobe Acrobat. Learn from it and use the advice to perform similar actions with your favorite PDF software.
1. Open the document in Adobe Acrobat.
2. Flatten all the complex pages into single-layered bitmaps (JPG).
3. Do a text-recognition (OCR scan) before uploading to ensure your document is optimized for search
And you're done!
For further assistance, check out Adobe's guide on how to compress your documents.