Messenger image size

Meta’s developer documentation for the Messenger Platform covers pictures sent by a Page: through its API, as a loose attachment or inside a template. It gives limits on file size and counts, one ratio for card images and general advice. It gives no pixel dimensions for an ordinary image in a chat bubble, and we found no third-party guide with an official figure either, so this page does not invent one.

For a plain image, the practical rule is to send a file big enough to look sharp on a phone and small enough to stay well under 8 MB. Meta’s own advice is to use colourful, high-resolution images and to check how the picture may be cropped in the message bubble.

The one ratio Meta names is for the generic template, the card with an image, a title, a subtitle and up to a few buttons. The documentation says Messenger scales or crops photos in that template that are not 1.91:1. At 1,910 pixels wide that is 1,000 pixels tall; at 1,200 wide it is about 628.

• A square product photo in a card is cropped or scaled, so keep the subject in the middle.
• A tall phone photo loses the most. Crop it to 1.91:1 yourself so you choose what is cut.
• Don’t use an animated GIF in a card. GIFs are accepted, but the card does not animate them.
• A carousel is up to 10 of these cards side by side, so make all the images the same shape.

Tip: Meta’s guidance is to avoid large amounts of text inside the image. Put the words in the card’s title and subtitle, or in a normal text message, where people can read them at any size.

Meta’s “Saving assets” page lists image, audio, video and file as supported types, up to 25 MB, then adds that an image sent from a URL is limited to 8 MB. The same page’s payload table repeats it: 8 MB for images and 25 MB for every other file type, after encoding. If you upload the picture from a file instead of a URL, the page still lists 25 MB as the general ceiling, but 8 MB is the figure to design for.

The 90-day rule applies to attachment IDs you saved to reuse. Meta says attachments already sent in a conversation never expire, and that uploading and sending in one step avoids the expiry. If a saved logo suddenly stops sending, an expired ID is the first thing to check.

Meta’s rules on timing still decide whether an image is sent at all. A Page can message someone within 24 hours of their last message. When the chat started from a comment, the first message is plain text, so an image or card comes after the person replies.

That order suits images anyway. Ask “Reply YES and I’ll send the price list” first. When they answer, send the picture or a card with a button, using the 1.91:1 shape and a file well under 8 MB.