Optimize PDFs for Email Attachment with PDF Compression

PDFs come in all shapes and sizes - some measured in kilobytes, others in megabytes, and large files can even reach multiple gigabytes. While most PDF use cases result in documents with file sizes in the range of hundreds of kilobytes to several megabytes, it is not uncommon for larger files to be the norm among specialized use cases. If your documents contain many high-resolution images, hundreds or thousands of pages, or other forms of large-scale information embedded in each file, you're likely going to run into challenges with document distribution. PDFs are complex documents, and the vast majority of these documents end up with excess and redundant content "under the hood." In other words, most PDFs are not optimized to be as small as they can be.

Sharing documents as email attachments is one of the most convenient and universally supported channels, whether through automated processes or direct collaboration. Yet, when PDFs are not optimized to be as small as possible, they have a higher risk of exceeding file size limitations for attachments, set by all major mail clients.

Email Client Attachment Limits

• Gmail: 25 MB total limit
• Yahoo: 25 MB total limit
• Outlook 20 MB total limit
• Office 365: 25 MB by default (can be modified by administrators to limits between 1 MB and 150 MB)

If you work with files that tend to reach megabytes in size - you're likely to run into these limits. pdfRest offers a workflow to compress PDFs, generally resulting in significantly smaller file sizes without impact to the overall viewing experience. While it requires a long series of behind-the-scenes operations to squeeze every last unneccessary byte out of the document file size, we've made the process simple for you, and fast too. Just choose between high, medium, and low compression levels, which offer a sliding tradeoff between size reduction and preservation of content fidelity.

pdfRest reduces file size by an average of 53% with the low compression setting through 68% with high compression and can reach up to 98% file size reduction for image-heavy PDFs. If you're running into email attachment limitations, pdfRest offers an easy way to integrate automated PDF compression into any workflow or application.

Code Example: High Compression   |   Load this into API Lab↗

    curl -X POST "https://api.pdfrest.com/compressed-pdf" \ 
        -H "Accept: application/json" \ 
        -H "Content-Type: multipart/form-data" \
        -H "Api-Key: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" \
        -F "file=@PATH_TO_FILE/PDF_Checker.pdf" \ 
        -F "compression_level=high" \
        

Compress PDF