Supported File Types and Size Limits for MMS

Want to add an image or video to your text campaign? This article covers which file types you can attach to an MMS and how large they can be.

Supported file types and sizes

Images

Videos

ⓘ Mobile carriers only deliver media up to about 1 MB. You can upload larger files, and CallHub automatically compresses them during upload so they meet carrier limits. Videos are compressed to 30 seconds or 1 MB.

✓ For the sharpest results, keep images under 1 MB and videos under 30 seconds before you upload. Heavy compression can reduce quality.

FAQs

Can I send a PDF through MMS? 
No. MMS does not support documents. Instead, upload the PDF somewhere online (for example, your website or a file-sharing service) and include the link in your message text.

Can I attach an audio file like an MP3? 
No. MMS supports only images and videos. If you want contacts to hear a recorded message, use a voice broadcast campaign or share a link to the audio in your message.

Why does my image or video look lower quality after sending? 
Carriers cap MMS media at about 1 MB, so CallHub compresses larger files to fit. Uploading files closer to that limit preserves more quality.

Does adding media change what my message costs? 
MMS is priced differently from SMS. See https://callhub.io/pricing/ for details.