- Mastodon supports up to 4 verified profile fields for clickable links — Edit Profile → Profile metadata → add label + URL.
- Verified links display a green checkmark if you add a link-back from your domain (rel="me" tag).
- For multiple destinations, use a link-in-bio service like UniLink as one of your 4 profile field links.
How to Add Profile Links on Mastodon
- Open your Mastodon instance (e.g., mastodon.social).
- Click your profile → Edit profile.
- Scroll to Profile metadata.
- Add up to 4 fields:
- Label — what you call the link (e.g., "Website", "Newsletter").
- Content — paste the URL.
- Click Save changes.
Your profile fields appear as a clean key-value table on your profile page.
Mastodon Bio Limits
| Field | Limit | Notes |
|---|---|---|
| Display name | 30 chars | Most instances |
| Bio (Description) | 500 chars | Plain text + clickable URLs |
| Profile metadata fields | 4 fields | Each field: 255 chars label + 255 chars URL |
| Profile picture | 2 MB max | Recommended 400x400 px |
| Header image | 2 MB max | Recommended 1500x500 px |
How to Get Verified Green Checkmark on Mastodon
Mastodon's "verification" is decentralized — you prove ownership of any URL by adding a link-back:
- Add the URL to your Mastodon profile metadata (e.g., yourname.com).
- On that URL's HTML, add:
<a rel="me" href="https://mastodon.social/@yourname">Mastodon</a>. - Mastodon detects the link-back and marks the field as verified (green checkmark).
This works for any URL — your website, GitHub, Substack profile, LinkedIn (workaround). Anyone visiting your Mastodon profile sees the green checkmark and trusts the link.
Add URLs in Bio Description
You can also add URLs in the main bio (Description) field. Mastodon auto-detects them and makes them clickable:
- 500-character bio supports many short URLs.
- Use the description for context; profile fields for verified links.
- URLs in description don't get the green checkmark.
Best Profile Field Setup for Creators
| Field 1 | Field 2 | Field 3 | Field 4 |
|---|---|---|---|
| Website (verified) | Newsletter | GitHub / Project | Link-in-bio (everything else) |
4 fields is tight but enough. If you have more destinations, use a UniLink URL as field 4 to consolidate.
How to Pin a Post on Mastodon
Pinned posts add another way to highlight links:
- Find a post with your key links.
- Click the 3-dot menu.
- Click Pin to profile.
- Up to 5 pinned posts at once.
Mastodon Verification vs Twitter Verification
| Feature | Mastodon | X |
|---|---|---|
| Verification cost | Free | $8-16/month (Premium) |
| How verified | Domain ownership (rel="me") | Pay subscription |
| Trust signal | Strong (proves you own a website) | Weak (anyone can pay) |
| Number of verifiable URLs | 4 (one per profile field) | 1 ("primary" link) |
Frequently Asked Questions
Can I add clickable links to Mastodon bio?
Yes — both in the Description (auto-detected URLs) and as Profile metadata fields (4 max with optional verification).
How do I get the green checkmark on Mastodon?
Add a rel="me" link-back from your website to your Mastodon profile. Mastodon detects it and marks the URL as verified. Free.
How many links can I add to Mastodon bio?
4 verified Profile metadata fields + unlimited URLs in the 500-char Description.
Does Mastodon penalize external links?
No. Posts with external URLs get normal reach. Mastodon doesn't have algorithmic ranking by default.
Can I change my profile fields anytime?
Yes — Edit profile → update Profile metadata → Save. Updates instantly.
Key Takeaways
- Profile metadata: up to 4 verified link fields (label + URL).
- Verify with rel="me" link-back from your website.
- Description (bio): 500 chars, supports clickable URLs.
- Pin up to 5 posts to your profile.
- Use a link-in-bio for destinations beyond 4 verified fields.
One link covers everything beyond your 4 fields
Use a UniLink URL as your 4th profile field — covers your courses, podcast, store, social media. Free with click analytics.