Free · Fast · Privacy-first

Split a PDF for Email Attachments

Most email providers cap attachments at 10-25MB, and recipients with stricter corporate inboxes may see anything over 10MB bounce.

⚡

Split into email-friendly file sizes

🔒

No attachment size workarounds needed

✨

Compress after splitting as an option

⚡

Free, no watermark

Cost: Free forever
Sign-up: Not required
Processing: In your browser
Privacy: Files stay local

FreeNo signupWhite-label

Add this PDF Splitter to your website

Drop the PDF Splitter into any page — blog post, product docs, intranet, school portal — with a single line of HTML. Your visitors get the full tool, processed entirely in their browser. No backend, no uploads, no signup.

Files stay 100% in the visitor's browser
Responsive — adapts to any container width
Free forever, no API key needed

Embed code

<iframe
  src="https://www.fixtools.io/pdf/pdf-splitter?embed=1"
  width="100%"
  height="780"
  frameborder="0"
  style="border:0;border-radius:16px;max-width:900px;"
  title="PDF Splitter by FixTools"
  loading="lazy"
  allow="clipboard-write"
></iframe>

<iframe
  src="https://www.fixtools.io/pdf/pdf-splitter?embed=1"
  width="100%"
  height="780"
  frameborder="0"
  style="border:0;border-radius:16px;max-width:900px;"
  title="PDF Splitter by FixTools"
  loading="lazy"
  allow="clipboard-write"
></iframe>

Attribution-friendly: a small "Powered by FixTools" link appears in the embed footer.

Gmail and Outlook attachment limits, when to split versus compress, and sending multi-part PDFs

Email attachment size limits vary by provider and account type. Gmail allows attachments up to 25MB per message; files larger than 25MB are automatically converted to Google Drive links. Outlook.com caps attachments at 20MB. Yahoo Mail allows 25MB. Microsoft 365 business accounts (Exchange Online) have a default limit of 25MB but administrators can raise this to a maximum of 150MB. Corporate Exchange servers often have lower limits set by IT policy, commonly 10MB or 20MB. Knowing your recipient's limit matters, a 22MB PDF that fits within Gmail's 25MB allowance may still exceed your recipient's corporate Exchange server limit of 20MB. When in doubt, target 15MB or less per attachment for maximum compatibility across mail systems.

The choice between splitting and compressing depends on whether the file is over the limit due to high page count or due to embedded image quality. A 50-page text-heavy PDF at 30MB is large because of document volume; splitting it into two 25-page files at roughly 15MB each is the cleaner solution. A 10-page scanned PDF at 45MB is large because of high-resolution images; compressing it from 45MB to 8MB is the cleaner solution because the recipient gets one file rather than multiple parts. The general rule: if the PDF has more than 20 pages and the size comes from volume, split it. If the PDF has 15 or fewer pages and the size comes from images, compress it first and only split if compression alone is insufficient.

When sending a split PDF in multiple email messages, include clear labeling to help the recipient reassemble or manage the parts. Name each file consistently: "Q3_Report_Part1of3.pdf," "Q3_Report_Part2of3.pdf," "Q3_Report_Part3of3.pdf." In the email body, note the total number of parts and the page ranges each covers. Send all parts in the same email thread so the recipient can find them together. If the recipient needs to reassemble the parts, direct them to FixTools PDF Merger, which can combine the parts back into a single document in their browser.

There are a few less obvious factors that change how much room you actually have for an attachment. Email systems base their size limit on the encoded message, not the raw file. MIME base64 encoding inflates binary attachments by roughly 33 percent before transmission, so a 20MB PDF travels as about 27MB of message payload. Most providers publish their limit as the encoded size, which is why a "20MB" file occasionally bounces on a server that advertises a 25MB cap. To stay safe, target raw file sizes that are at least 20 percent below the published limit. Also remember that some receiving systems strip or quarantine attachments based on signature scanning policies, particularly in healthcare, legal, and finance environments. If a previous send has failed silently, ask the recipient to whitelist your sender address or to confirm whether their gateway accepts PDF attachments at all before you split a sensitive document into multiple parts and send it.

Gmail attachment size limits (Google Support)Outlook attachment size limits (Microsoft Support)Microsoft 365 message size limits

How to use this tool

💡

Upload your large PDF and split it by page range or equal-size chunks so each part fits within your email provider's attachment limit. Alternatively, use PDF Compressor to shrink the file without splitting.

How It Works

Step-by-step guide to split a pdf for email attachments:

1
Check your email size limit
Gmail allows 25MB per message, Outlook.com allows 20MB, Yahoo allows 25MB, and Microsoft 365 Exchange Online defaults to 25MB but can be capped lower by your IT administrator. Confirm the limit for both your sending account and your recipient's mailbox if known, since the smaller of the two governs delivery.
2
Upload your large PDF
Open the FixTools PDF Splitter in any browser and drag the oversized PDF onto the upload area. The file stays in your browser tab, nothing is uploaded to a remote server, so even sensitive financial or legal documents can be split without leaving your machine.
3
Split into equal-size parts
Choose the "split every N pages" option and pick a page count that divides your file into parts under the target limit. For a 60MB, 240-page PDF aimed at a 20MB cap, split every 80 pages to produce three roughly 20MB parts. Verify each output file size after download before sending.
4
Send parts in separate emails
Attach each part to a separate email message in the same conversation thread. In the subject line, append "Part 1 of N," "Part 2 of N," and so on. In the body, list the page ranges each attachment covers and link the recipient to PDF Merger if they want to recombine them.

Real-world examples

Common situations where this approach makes a real difference:

Accountant

An accountant needs to email a 55MB, 180-page annual financial report to a client whose corporate email has a 20MB attachment limit. She splits the report into 4 equal parts of 45 pages each, producing four files of approximately 13MB each. She sends each part in a separate email with the subject line "Annual Report [Part 1 of 4]" and a note in the body directing the client to the page range covered. She also includes a final summary message linking back to FixTools PDF Merger so the client can rejoin the parts before archiving the report in their internal document management system.

Architect

An architect has a 40MB, 25-page construction drawing set that needs to be emailed to a contractor. The drawing set is large due to high-resolution CAD exports at 600 DPI. Rather than splitting (which would separate related drawings), he runs the PDF through the PDF Compressor first. Compression at medium quality reduces it from 40MB to 9MB, which fits in a single Gmail attachment without splitting. He spot-checks a few pages at 100 percent zoom to confirm that dimension callouts and door schedules remain legible, then attaches the compressed file with a brief note explaining the compression so the contractor knows to request a higher-resolution version if they need to print at full scale.

Legal assistant

A legal assistant needs to email a 65-page, 38MB deposition transcript to three attorneys. Gmail's 25MB limit prevents attaching the full file. She splits it into two parts: Part 1 covers pages 1-35 (18MB) and Part 2 covers pages 36-65 (20MB). Both parts are under 25MB and sent in two separate emails. She notes the page ranges in each email subject line and CCs the case docket address so both halves are filed under the same matter number. Because the firm's outbound gateway encodes attachments with base64, she leaves a margin of about 5MB under the limit on each part to avoid encoded-size bounces.

Non-profit coordinator

A non-profit coordinator needs to send a 30MB grant application PDF package via a state agency's email portal that has a 10MB attachment limit. She splits the application into 4 parts by section: cover letter and executive summary (pages 1-8, 4MB), program description (pages 9-21, 9MB), budget and financials (pages 22-35, 10MB), and attachments (pages 36-50, 7MB). Each part stays under the 10MB limit. She names the files with the agency's required convention (Org_GrantID_Section_PartXofY.pdf) and sends each part as a separate submission email, retaining bounce-back receipts as proof of timely filing in case the agency questions whether any section arrived before the deadline.

Pro tips

Get better results with these expert suggestions:

Try compression before splitting, one file is always better than multiple

A recipient who receives one compressed PDF has a simpler experience than one who receives three parts and needs to reassemble them. Before splitting, run your PDF through the FixTools PDF Compressor. For scanned documents and image-heavy PDFs, compression often achieves 60-80% size reduction. A 45MB scanned report may compress to 7MB, eliminating the need to split entirely. Only split if compression alone cannot bring the file under the email limit, or if the file is text-heavy and already optimized so further compression would harm legibility.

Calculate part sizes before uploading

Divide your file size by the number of parts you plan to create before uploading. A 60MB PDF split into 3 parts averages 20MB per part, within Gmail's 25MB limit but over Outlook's 20MB limit. If you are unsure of the recipient's limit, target 15MB per part for safe delivery across all common email systems. Adjust your pages-per-part value accordingly.

Name split files with part numbers and page ranges

Use a naming convention like "ProjectReport_Part1of3_Pages1-45.pdf" rather than the default "part_01.pdf." Descriptive names help the recipient track which parts they have received and which pages each covers. When the recipient later needs to reassemble the parts, clearly named files make the merge order obvious without having to open each file to check.

Use a cloud link for very large files instead of splitting

If your PDF is over 100MB and splitting would produce more than 5 parts, consider uploading to Google Drive, Dropbox, or OneDrive and sharing a link instead. Google Drive shares files of any size without size limits. For confidential documents, set the sharing permission to "anyone with the link can view" and include an expiration date. This is often more practical than sending 6+ email attachments.

FAQ

Frequently asked questions

You have two options: split the PDF into smaller parts that each fit under the size limit, or compress the PDF to reduce its total size. Splitting creates multiple files that the recipient receives separately. Compression creates one smaller file. Try compression first, it is simpler for the recipient. If the compressed file is still too large, then split it into parts. Use FixTools PDF Compressor for compression and PDF Splitter for splitting.

Gmail allows attachments up to 25MB per message. For files between 25MB and 10GB, Gmail automatically inserts a Google Drive link instead of a direct attachment, the file is uploaded to your Google Drive and the recipient receives a link to view or download it. For files over 25MB where you want a true attachment (not a link), you must split or compress the file below 25MB.

Outlook.com allows attachments up to 20MB per message. Microsoft 365 business accounts using Exchange Online have a default limit of 25MB, but organization administrators can set lower limits. On-premises Exchange servers commonly have limits of 10-20MB set by IT policy. If you are unsure of your recipient's Exchange limit, target 15MB or less per attachment file to ensure delivery across all common configurations.

Compress first. Compression is simpler because the recipient gets one file rather than multiple parts to manage and potentially reassemble. For scanned PDFs and image-heavy documents, medium compression often reduces file size by 60-80%, bringing a 40MB file down to 8-12MB. Only split if compression alone cannot bring the file under the email limit, or if the PDF contains sensitive sections that should not all be sent to the same recipient.

Yes. The recipient can use the FixTools PDF Merger (at fixtools.io/pdf/pdf-merger) to combine the parts back into one document. They upload all the part files, arrange them in order, and download the merged PDF. The merged result is identical to the original. Direct your recipient to FixTools PDF Merger when sending split parts and note the correct order (Part 1 first, then Part 2, etc.).

Calculate pages per MB from your original file. Divide the total page count by the file size in MB to get approximate pages per MB. For example, a 180-page, 54MB PDF has about 3.3 pages per MB. To produce parts under 20MB, target approximately 60 pages per part (60 pages x 0.3MB/page = 18MB). For scanned PDFs, the math may differ significantly by section depending on image content density. Split into your calculated chunks, then check each output file size.

Yahoo Mail allows attachments up to 25MB per message, the same as Gmail. However, Yahoo Mail does not automatically provide a cloud link alternative for oversized files the way Gmail does. If your file exceeds 25MB, you must split or compress it before attaching. Yahoo Mail also occasionally enforces lower limits for recipients with full mailboxes or in certain corporate environments.

If your split parts are still over the email limit, combine splitting with compression. Split the file into parts first, then run each part through the FixTools PDF Compressor. For example, a 200MB scanned PDF split into 4 equal 50-page parts produces four 50MB files. Compressing each 50MB file at medium quality typically reduces them to 8-12MB each, well within any email limit. This two-step process handles even very large scanned documents and keeps each part safely below the encoded-size threshold that providers actually enforce on the wire.

Most modern mail clients group messages with the same subject line into a single conversation thread, which keeps the parts visually adjacent. To make ordering explicit, include "Part 1 of N," "Part 2 of N," and so on in the subject line so each message is unambiguous even when sorted independently. Inside the body, restate the page ranges and the intended merge order. If the recipient uses an older client that does not thread by subject, they will still see all messages from you within a few minutes of each other and can sort by send time or by the part number in the subject.

No. The PDF Splitter runs entirely in your browser using JavaScript and the PDF-lib library, so your file is never uploaded to a FixTools server. The split operation happens in memory on your own device, and the resulting part files are generated locally and offered as direct browser downloads. Nothing about the document leaves your machine. This is particularly important when the file you are splitting contains personally identifiable information, financial statements, medical records, or anything else covered by data protection regulations like HIPAA, GLBA, or GDPR that restrict third-party processing.