PDF Compressor for Email

About the PDF Compressor for Email

Add a PDF and get it back under 20 MB, small enough to attach to an email in both Gmail and Outlook: a personal Gmail account takes 25 MB of attachments, and Outlook for Windows stops at 20 MB with an internet mail account. The tool tries the settings for you — first lossless optimisation, then photos and scans re-encoded at lower quality and resolution — and keeps the sharpest file that fits, while text, fonts and drawings stay exactly as they are, still selectable and searchable. For Gmail alone, choose 25 MB.

PDFs that big usually hold scans or photos, which shrink the most. Everything runs in your browser: the PDF is never uploaded. Without a pass, the free preview shows the size your PDF reaches and compares up to 3 of its pages with your original, watermarked; the PDF downloads with a pass, or after unlocking this result.

Email attachment limits

• Gmail, personal accounts: 25 MB of attachments per email. Over that, Gmail takes the files out and adds a Google Drive link instead.
• Outlook for Windows with an internet mail account (POP3, IMAP or HTTP): 20 MB of attachments.
• Work and school mailboxes have the limits their administrator sets. A Microsoft 365 mailbox sends messages of up to 35 MB unless it was set otherwise, and a message grows by about a third on its way out of Microsoft’s data centres, as its attachments are encoded.

Every limit counts all the attachments of one email together. Sources: Gmail Help: Send attachments with your Gmail message, Microsoft Learn: Outlook’s attachment size limit, Microsoft Learn: Exchange Online limits.

20 MB: 20,000,000 or 20,971,520 bytes?

Outlook states its limit as 20,480 KB, which is 20,971,520 bytes, and Gmail’s 25 MB is larger still. This page makes the file at most 20,000,000 bytes, under both.

What gets smaller

• Scans and photos shrink the most: the search lowers their JPEG quality and resolution only as far as the limit needs, and the result says what it did to them.
• Text, fonts and drawings are kept exactly as they are, so the text stays sharp, selectable and searchable.
• Greyscale helps black-and-white documents most: contracts, letters, forms and ID scans.

When it still doesn’t fit

If even the strongest settings leave the PDF over the limit, the tool shows why and offers page images as a last step. Sending only the pages that are needed often works better: PDF Page Extractor and Split PDF. Gmail also turns attachments over 25 MB into a Google Drive link by itself.

Other sizes

Compress PDF to Size takes any limit, and form uploads have pages of their own: 200 KB · 300 KB · 500 KB. A video for an email: Compress Video for Email.

How this compares

• Runs on your device: your browser tries every setting itself; the PDF is never uploaded.
• See it before you pay: the free preview shows the size your PDF reaches and compares up to 3 of its pages with your original, with a MySmartCoPilot watermark; the PDF you download with a pass, or after unlocking it, holds only your own pages.
• You don’t need an account: no sign-up, no email address and nothing to install.

Limitations

• Password-protected PDFs must be unlocked first with Unlock PDF. A digitally signed PDF loses its signature when it is changed.
• Page images, the last step, remove selectable text, links and form fields; the original file is never changed.
• Files up to 200 MB. Large, photo-heavy PDFs can take a few minutes, especially on phones. The first use downloads the PDF engines, so it needs an internet connection once.

Privacy

On this device: nothing is sent

Everything happens in your browser. What you enter or open here is not uploaded or stored by MySmartCoPilot.