Split PDF into 20MB Parts
Use the Outlook 20MB preset to split large PDFs into attachment-ready parts while keeping page order.
No quality loss, page order preserved.
Email presets: Gmail 25MB, Outlook 20MB, Outlook.com 25MB, plus custom size.
Example: 38 MB PDF -> 2 parts under 20 MB (keeps page order).
How it works
Set limit
Choose Gmail, Outlook, Outlook.com, or a custom MB value.
Split
We generate parts that fit the limit.
Download
Get a zip of split PDFs.
Split to 20MB FAQ
Is 20MB safer for Outlook?
Yes. Many Outlook accounts and corporate mail servers cap attachments around 20 MB. Use the 20MB preset when in doubt.
Can I compress instead of splitting?
Try email-ready compression first. If it still does not fit, splitting is the safest option.
Outlook-sized PDF parts
Why split for Outlook limits
Outlook limits can be strict, especially in corporate environments. Splitting preserves quality by keeping each part under the cap without forcing aggressive compression.
This is ideal for scan-heavy documents, long reports, and portfolios where every page needs to stay clear.
Predictable part sizes
PDFThin groups pages to keep each part under 20 MB and maintains page order. We leave a safety margin so attachments stay under the limit after encoding.
You get a ZIP with numbered parts that are ready to attach in separate emails.
Share with less back-and-forth
Send parts sequentially or across multiple messages based on your workflow. Recipients can open each part immediately without extra tools.
If you need a single file, try compression first, then split only if needed.
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