---
title: "Email Domain Check API"
url: "https://lookvalid.com/products/email-domain-check.md"
canonical_url: "https://lookvalid.com/products/email-domain-check"
last_updated: "2026-10-22"
type: "product"
summary: "Checks the domain behind an email address: MX records, SPF and DMARC policies, and whether the address uses a disposable domain."
related: ["https://lookvalid.com/pricing.md", "https://lookvalid.com/docs/api/email-domain-check.md"]
---

# Email Domain Check API

Checks the domain behind an email address: MX records, SPF and DMARC policies, and whether the address uses a disposable domain.

Checks the domain behind an email address: MX records, SPF and DMARC policies, and whether the address uses a disposable domain, a free mailbox provider or a role mailbox such as info@ or support@. It never contacts the mail server, so it cannot confirm that a mailbox exists.

## Facts

- Endpoint: `POST https://YOUR_API_HOST/v1/email-domain-check`
- Price: 1 credit per address checked
- Charged: Only when a lookup finds something
- Cache: repeating the same lookup within 7 days is free

## Example request

```sh
curl -X POST https://YOUR_API_HOST/v1/email-domain-check \
  -H "Authorization: Bearer $LOOKVALID_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"email":"someone@example.com"}'
```

## Response

The `data` object has 15 named fields. Every response also lists the sources behind the result, the credits charged and whether it was served from your cache.

| Field | Type | Description |
| --- | --- | --- |
| `email` | string or null | Normalized address (lowercase, punycode domain); null for a domain-only lookup |
| `syntax_valid` | boolean or null | True for an email that passed the syntax check; null for a domain-only lookup (bad syntax is rejected as invalid input) |
| `domain` | string |  |
| `mx_records` | array of object | Sorted by priority, then host name |
| `has_mx` | boolean |  |
| `null_mx` | boolean | True when the domain publishes a null MX ("0 ."), meaning it accepts no mail |
| `implicit_mx` | boolean | True when there is no MX but an A or AAAA record, so senders fall back to the host itself |
| `spf` | object |  |
| `dmarc` | object |  |
| `disposable` | boolean |  |
| `free_provider` | boolean |  |
| `role_account` | boolean or null | Null for a domain-only lookup |
| `smtp_checked` | false | The mail server is never contacted, so mailbox existence is not verified |
| `deliverability_signal` | "good" | "risky" | "undeliverable" |  |
| `deliverability_reasons` | array of object |  |

## Priced in credits

| Case | Charge |
| --- | --- |
| Found | 1 credit |
| Nothing found | 0 credits |
| Repeat inside 7 days | 0 credits |
| Errors and invalid requests | 0 credits |

## Questions

### How much does Email Domain Check cost?

1 credit per address checked. Credits come out of the one balance shared by every LookValid product.

### Am I charged when nothing is found?

No. When the lookup runs and finds nothing, it returns found: false and costs 0 credits. An error costs nothing either.

### How long are results cached?

For 7 days, per account. Repeating the same lookup inside that window returns cache_hit: true and costs 0 credits.

### Which API key do I use?

The same key as every other product. Send it as a Bearer token in the Authorization header. Email hello@lookvalid.com and we set up your account and send the key.

## Related products

- [Phone Numbering-Plan Validation](https://lookvalid.com/products/phone.md): Checks a phone number against its country's numbering plan and returns E.164, national and international formats, the country and the number type the plan assigns (mobile, fixed line, toll free, VoIP and others).
- [Country Calling Codes](https://lookvalid.com/products/country-code.md): Looks up a country by calling code (+44), ISO region (GB) or English country name and returns the calling code, every region that shares it, national number lengths, trunk and international dialing prefixes, example numbers and the leading digits of mobile and fixed-line numbers where the numbering plan defines them.
- [IP Intelligence](https://lookvalid.com/products/ip.md): Location and network details for an IPv4 or IPv6 address (country, region, city, time zone, ASN and network owner) with risk flags from open lists such as Tor exit nodes and cloud provider ranges.

Full request and response fields: [Email Domain Check reference](https://lookvalid.com/docs/api/email-domain-check.md).

## Related

- [Plans, trial and credit pricing](https://lookvalid.com/pricing.md)
- [Email Domain Check reference](https://lookvalid.com/docs/api/email-domain-check.md)