Split a PDF for Email Attachments

Step 1: Pick the limit that matches your email

Choose Gmail 25 MB or Outlook 20 MB presets. If you are unsure, use a slightly lower custom size.

Lower targets improve delivery when multiple attachments are included.

Step 2: Split with PDFThin

Use Split by size to create attachment-ready parts. The tool preserves page order and names parts clearly. Each part stays under the limit so you can attach them without errors.

Step 3: Review the output

Open a part to confirm it displays correctly. You can preview several parts to ensure page flow.

If parts feel too large, lower the size target and split again.

Step 4: Send with context

Include a short message that explains the PDF is split and lists the number of parts.

This helps recipients keep everything in order and avoids confusion.

Will recipients need special software?

No. Each part is a standard PDF and can be opened with any PDF reader.

Can I merge the parts later?

Yes. You can merge parts after downloading or use any PDF merge tool.

Do parts stay under the limit?

Parts are generated to stay under your selected limit, with a safety margin.

Attach in a single email if possible

If your provider allows, attach all parts in one email to keep the conversation simple.

If not, send multiple emails and label the subject with part numbers.

Keep filenames short

Short filenames reduce clutter for recipients and make it easier to follow the sequence.

Use a consistent naming format like Report-Part-01.pdf.

All PDF tools

Browse every PDFThin tool in one place.

Email-ready compression

Shrink PDFs to Gmail/Outlook limits with quality control.

Split by size

Split large PDFs into size-safe parts.

Organize PDF

Merge, rotate, delete, reorder, and split pages.

All PDF guides

Browse every step-by-step PDF guide.

Compress PDF for email (complete)

Step-by-step workflow for Gmail 25MB and Outlook 20MB limits.

Reduce scanned PDF size

Keep text readable while shrinking scanned documents.

Split PDF by size

Create parts that stay under a target MB limit.

Rotate PDF pages online

Fix page orientation for sideways scans or photos.