Compress PDF vs Split PDF: which should you use?

When a PDF is too big to email or upload, you have two levers: make the file smaller (Compress) or make several smaller files (Split). Which one wins depends on whether the recipient needs one document or is fine with a few.

Compress PDF re-serializes object streams and, for scans, downsamples embedded images. You keep one file and the reader keeps one document, but you trade some image fidelity.

Split PDF is lossless — every output looks identical to the source — but the recipient has to open multiple files. Use it when the file is mostly text and compression won't help much.

Feature comparison

Feature	Compress PDF	Split PDF
Result	One smaller PDF	Several PDFs, each under the limit
Quality loss	Slight for scans, none for text	None — fully lossless
Recipient experience	One attachment, one file to open	Multiple attachments to download in order
Best for	Scanned or image-heavy PDFs	Text-only PDFs that already compress poorly
Typical size drop	40–80% for scans, 10–30% for text	N/A — sum of parts ≈ original

Our verdict

Reach for Compress PDF first — it keeps the file as one attachment. If the PDF is already text-only and compression only trims 10%, Split it into logical chunks (chapters, invoices, quarters) and label each part clearly.

Frequently asked questions

What if compression alone doesn't fit under Gmail's 25 MB limit?+

Run Compress PDF first, then Split PDF on the compressed output. That combination almost always fits large scanned bundles under mail-server limits.

Does splitting a PDF affect its searchability?+

Each split file keeps its own text layer, so full-text search works inside each part. You lose the ability to search across the whole document as a single file.