Your avatar is an icon that is displayed next to your posts and is part of your visual identity. You can upload an avatar as a PNG, GIF, or JPG image up to 2MB in size. This image will be downscaled to 400x400.
Your header is a banner image shown at the top of your profile, as well as in profile cards used in follow lists and account directories. You can upload a header as a PNG, GIF, or JPG image up to 2MB in size. This image will be downscaled to 1500x500.
Enabling the bot flag will add a bot icon to your profile. This icon will let others know that your profile may perform automated actions, or might not be monitored by a human. Other software may choose to treat bot profiles differently, but Mastodon currently treats the bot flag as a visual indication only.
Profile metadata is a way to add extra information to your profile that is easy to skim. You have 4 rows where you can define the label and the value. For example:
| Label | Content |
| :--- | :--- |
| Age | 25 |
| Country | Germany |
| Pronouns | he/him |
| Website | https://example.com |
It’s completely up to you what you put there. The content can contain mentions, hashtags, custom emojis and links.
Document-based verification and blue ticks are not possible without a central authority. However, Mastodon can cross-reference the links you put on your profile to prove that you are the real owner of those links. In case one of those links is your personal homepage that is known and trusted, it can serve as the next-best-thing to identity verification.
If you put a link in your profile metadata, Mastodon checks if the linked page links back to your Mastodon profile. If so, you get a verification checkmark next to that link, since you are confirmed as the owner.
Behind the scenes, Mastodon checks for the `rel="me"` attribute on the link back. Likewise, Mastodon puts `rel="me"` on the links within profile metadata.
Because Mastodon can be self-hosted, there is no better way to verify your identity than to host Mastodon on your own domain, which people already trust.