CMass lets you insert images and video thumbnails directly into your email body. The media toolbar appears above each body text area in the Template tab and in every follow-up stage.
Inserting an image
Click '🖼 Image' in the toolbar. You have two options:
Option 1: Paste a URL
If your image is already hosted somewhere (Imgur, a CDN, Google Drive public link, your own server), paste the URL in the field and click Insert. The image is added to your email body as an HTML img tag pointing to that URL.
Option 2: Upload from your device
Click 'Upload from device' and choose a file. CMass uploads the image to imgbb (a free image hosting service) and inserts the hosted URL automatically. Image files must be under 5 MB.
Inserting a video thumbnail
Email clients don't support embedded video. The industry-standard workaround is to insert a clickable thumbnail image that links to the video. CMass handles this automatically for YouTube and Vimeo:
- 1Click '🎬 Video' in the media toolbar
- 2Paste a YouTube or Vimeo URL
- 3CMass fetches the video thumbnail and shows a preview with a play button overlay
- 4Click Insert — the thumbnail is added to your email with a link to the video
When a recipient clicks the thumbnail in the email, they're taken directly to the video on YouTube or Vimeo.
Best practices for email images
- ▸Keep images under 100 KB for fast loading — compress with TinyPNG or Squoosh before uploading
- ▸Always include alt text (CMass adds an empty alt attribute; edit the HTML if you need a specific description)
- ▸Don't make your entire email one big image — most spam filters penalize image-heavy emails with little text
- ▸Test on mobile — many email clients show images at full width on small screens