# Managing Custom Blocklists

> Create and manage blocklist entries to instantly block known bad actors.

**Category:** dashboard | **Last updated:** March 13, 2026

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Custom blocklists let you maintain a list of emails, domains, and IP addresses that should be automatically blocked. This feature is available on the **Starter plan** and above.

## How blocklists work

When you add an entry to your blocklist, every future validation request checks against it. If the user's email, domain, or IP matches a blocklist entry, the `custom_blocklist` check fails and the risk score increases significantly.

## Adding entries via the dashboard

1. Go to [Blocklists](/app/blocklists) in your dashboard
2. Click **Create Entry**
3. Choose the type: **Email**, **Domain**, or **IP**
4. Enter the value (e.g., `spammer@example.com`, `shadydomain.com`, or `203.0.113.50`)
5. Add an optional reason (for your own reference)
6. Set a severity (1–10) — higher severity contributes more to the risk score
7. Save

## Adding entries via the API

You can also manage blocklists programmatically:

```bash
# Add an entry
curl -X POST https://api.fidro.io/api/blocklist \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "type": "email",
    "value": "spammer@example.com",
    "reason": "Repeated chargeback fraud",
    "severity": 8
  }'

# List entries
curl https://api.fidro.io/api/blocklist \
  -H "Authorization: Bearer YOUR_API_KEY"

# Delete an entry
curl -X DELETE https://api.fidro.io/api/blocklist/ENTRY_ID \
  -H "Authorization: Bearer YOUR_API_KEY"
```

## Blocklist types

| Type | Matches against | Example |
|------|----------------|---------|
| **Email** | Exact email address | `fraud@example.com` |
| **Domain** | All emails from that domain | `example.com` (blocks any `@example.com` address) |
| **IP** | Exact IP address | `203.0.113.50` |

## Severity levels

Severity controls how much the blocklist match contributes to the risk score:

| Severity | Impact |
|----------|--------|
| 1–3 | Low — adds a small amount to the score |
| 4–6 | Medium — noticeable score increase |
| 7–10 | High — likely pushes the score into "block" territory |

## Public vs private entries

When creating an entry, you can mark it as **public**. Public entries are shared with the wider Fidro community, helping protect all users. Private entries only apply to your account.