When I sign up to a web service, I don't want to faff around uploading an image to use as my avatar. I want that service to look at my email address or social-sign-in and automatically pick up my preferred graphic.

Here's how I see it working.

1. A user signs in to a service with the email address username@example.com
2. In a similar way to WebFinger, the service makes a request to:
   • example.com/.well-known/avatar?resource=acct:username@example.com
3. If the request's Accept header has a MIME type of image/*, then the server immediately returns an image.
4. If the request's Accept header has a MIME type of application/json, then the server can return a WebFinger-style document with "rel":"http://webfinger.net/rel/avatar" and, perhaps, a list of different images, formats, and sizes.

This makes it incredibly simple for people to use the same avatar everywhere.

It also means that if you're designing a service which publicly shows usernames, you can make avatars available without an expensive API call. For example, Twitter could make user's avatars available at: twitter.com/.well-known/avatars?resource=acct:edent

But what about...?

This is a sketch of an idea. I'd like to know if people think it is useful before I take it any further.

I don't think it breaches privacy - a user's image is public on all services anyway.

Users should still be given the option of changing their avatar if they want.

A service shouldn't expose the user's email address - they should proxy the image.

Anything else I should have thought of?

Updates

To stave off some common points raised.

• No this isn't like Gravatar. That works by being a 3rd party service and using the MD5 of your email address.
• No this isn't like Libravatar. See above.
• No this isn't like WebFinger. That only returns JSON.
• No this isn't like h-card. That requires a server to parse HTML in order to find an image.
• No this isn't like BIMI. That's expensive and only supports SVG.

I always used avatars.io - but sadly that service has bitten the dust. So I've switched to unavatar.

It's dead easy to use. https://unavatar.now.sh/twitter/edent will return @edent's avatar. You can use GitHub, Facebook, Gravatar, Instagram, Telegram, YouTube, SoundCloud, and a couple of other providers.

Simple to use, and easy to embed in an <img> element.

It's also open source and looks pretty easy to deploy if you want to host it yourself.

Why is this needed?

In an ideal world, there would be a standard for where to find a user's avatar. Possibly a .well-known resource. Until then, we have to make do with 3rd party services playing intermediary.

I was lucky enough to go to Number 10 Downing Street for a meeting a few weeks ago. A perfect opportunity for a photo of me by that famous door.

Being the vain man that I am, I wanted to set it as my avatar photo. But Twitter and other social networks now use circular avatars.

The "10" has been obliterated and part of my head is missing.

So I've created a quick way to preview avatar images to see how they'll look on both squares and circles. It places a simple overlay on top of your image - like so:

Images can be panned around and zoomed using the mouse.

You can play with the demo

This is only a Minimum Viable Prototype - pull requests welcome!