The Mailpro Builder accepts a wide range of file types for images, attachments and downloadable resources. Each type has a maximum size designed to balance email deliverability with rich content. The reference table below covers everything you can upload from the editor or the file manager.

Why size matters: Heavy emails get throttled or filtered as spam. The total HTML weight (including embedded images) should stay under 100 KB; large assets are best linked, not embedded.

Supported image formats

Format Max size Best use
JPG / JPEG 5 MB Photos, hero banners
PNG 5 MB Logos, screenshots, transparent images
GIF (animated or static) 5 MB Light animations, icons
WebP 5 MB Modern responsive images (limited Outlook support)
SVG 1 MB Vector logos and icons

Document and downloadable file formats

Format Max size Typical use
PDF 10 MB Catalogs, brochures, tickets
DOC / DOCX 10 MB Editable documents
XLS / XLSX 10 MB Spreadsheets, price lists
CSV 10 MB Data files, contact imports
ZIP 10 MB Bundled files, multi-document downloads
ODS 10 MB Import lists
VCF 10 MB Import lists

Audio and video

Direct upload of audio/video into emails is not recommended — most clients block them. Instead, host on YouTube/Vimeo and link from a thumbnail. The Mailpro Builder has dedicated YouTube and Vimeo blocks that auto-generate clickable thumbnails.

Where the files are stored

Every uploaded file is hosted on Mailpro’s CDN with HTTPS and a stable URL. Files remain available as long as the account is active. Read more about image and file hosting.

Important: Mailpro automatically renames uploaded files to avoid spaces, accents and special characters. The original name is kept in the alt-text. See file upload renaming.

Best practices

Compress images before upload (TinyPNG, Squoosh, ImageOptim) to keep emails snappy. Use SVG for crisp scalable logos. For attachments larger than 10 MB, link to a cloud share (Google Drive, Dropbox) instead of attaching.

Build emails that load fast

Mailpro’s drag-and-drop editor includes an integrated image editor to crop, resize and optimize your assets in one place. Read the full file size FAQ.

 

Previous question

   

Next question

You might also be interested in:

Is There a Size Limit for a Newsletter?

Yes — and the limit that hurts most isn't from your ESP, it's from Gmail clipping at 102 KB of...

Read more

Is it possible to host my images and files on Mailpro?

Yes — Mailpro includes free, unlimited hosting for your images, PDFs and other campaign files. Pro tip: every hosted file gets...

Read more

File upload: how and why we rename your files

When you upload an image or document to your Mailpro account, the original filename is replaced by a unique random...

Read more

How to resize an image in a newsletter?

Mailpro's drag-and-drop editor resizes your images in just a few clicks — no external software needed. Pro tip: keep each image...

Read more

File Sizes and Extensions Supported by Mailpro Builder

The Mailpro Builder accepts a wide range of file types for images, attachments and downloadable resources. Each type has a...

Read more

Unleash the Power of Professional Email Marketing

Secure, scalable, and built for impact. Join Mailpro™ today and enjoy 500 free credits to send your first campaign.
Start Sending for Free