> ## Documentation Index
> Fetch the complete documentation index at: https://docs.datalinkapis.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Deliverability

> Deep email deliverability check — SMTP handshake, spam trap detection, and disposable screening.

## Endpoint

```
POST /v1/deliverability
```

**Cost:** 1–3 credits per request (dynamic)

Built for email senders who need to protect their sender reputation. Use Deliverability when a bounce or spam trap hit has real consequences — cold outreach campaigns, transactional flows, or any send where deliverability SLAs matter. It goes further than standard email validation by running an extended SMTP handshake and catch-all detection, giving you a `confidence` rating you can act on before you send.

This is a deeper version of the standard email validation. Where `/v1/email` confirms basic reachability, `/v1/deliverability` runs an extended SMTP handshake, cross-references known spam trap databases, and applies additional disposable provider detection. Adding a `phone` field extends the check to include phone HLR.

| Fields provided   | Credits charged |
| ----------------- | --------------- |
| `email` only      | 1               |
| `email` + `phone` | 3               |

## Request body

```json theme={null}
{
  "email": "hello@datalinkapis.com",
  "phone": "+447700900123"
}
```

| Field   | Type   | Required | Description                                                      |
| ------- | ------ | -------- | ---------------------------------------------------------------- |
| `email` | string | Yes      | The email address to check                                       |
| `phone` | string | No       | Phone number in E.164 format — adds phone HLR check (+2 credits) |

## Example request

```bash theme={null}
curl -X POST https://api.datalinkapis.com/v1/deliverability \
  -H "Authorization: Bearer dl_live_YOUR_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "email": "hello@datalinkapis.com" }'
```

## Response

```json theme={null}
{
  "email": "hello@datalinkapis.com",
  "deliverable": true,
  "confidence": "high",
  "syntax_valid": true,
  "mx_found": true,
  "smtp_valid": true,
  "spam_trap": false,
  "disposable": false,
  "catch_all": false,
  "role_account": false,
  "free_provider": false,
  "domain": "datalinkapis.com",
  "credits_used": 3
}
```

## Response fields

| Field           | Type    | Description                                                      |
| --------------- | ------- | ---------------------------------------------------------------- |
| `email`         | string  | The address that was checked                                     |
| `deliverable`   | boolean | Whether the address is likely to accept mail                     |
| `confidence`    | string  | Confidence level: `high`, `medium`, or `low`                     |
| `syntax_valid`  | boolean | RFC 5321 syntax check                                            |
| `mx_found`      | boolean | Whether a valid MX record exists                                 |
| `smtp_valid`    | boolean | Whether the extended SMTP handshake succeeded                    |
| `spam_trap`     | boolean | Whether the address matches a known spam trap                    |
| `disposable`    | boolean | Whether the domain is a disposable provider                      |
| `catch_all`     | boolean | Whether the domain accepts all addresses regardless of existence |
| `role_account`  | boolean | Whether this is a role address (info@, support@, etc.)           |
| `free_provider` | boolean | Whether this is a free consumer email provider                   |
| `domain`        | string  | Domain portion of the address                                    |
| `credits_used`  | integer | Credits deducted — 1 (email only) or 3 (email + phone)           |

## When to use vs `/v1/email`

|                     | `/v1/email` (1cr) | `/v1/deliverability` (up to 3cr) |
| ------------------- | ----------------- | -------------------------------- |
| Syntax check        | ✓                 | ✓                                |
| MX lookup           | ✓                 | ✓                                |
| SMTP check          | Basic             | Extended handshake               |
| Spam trap detection | —                 | ✓                                |
| Catch-all detection | —                 | ✓                                |
| Confidence score    | —                 | ✓                                |

Use `/v1/deliverability` when sending to a list where a bounce or spam trap hit would have significant consequences — e.g. cold outreach or transactional flows with strict deliverability SLAs.