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How can marketing teams check their lists and sending domains before a campaign?

Check the domain behind every address on your list, the authentication records on the domains you send from, and the numbers you plan to text. You send to addresses whose domains can receive mail and fix your own sender setup first.

The problem

A campaign list collects entries from forms, events and imports, and some of them are mistyped, throwaway or role addresses nobody reads. They count in the send and they drag down the numbers you report afterwards.

The domains you send from matter as much as the ones you send to. Missing SPF or DMARC records are easy to overlook until a send lands in spam folders, and the check takes seconds when it is a lookup.

Teams also wrap up other people's sites: partner pages, creator profiles and landing pages. Reading what a page really says, and where its links go, is a repeated chore that suits a script.

The FBI Internet Crime Complaint Center received 193,407 phishing and spoofing complaints in 2024, the largest number of complaints of any crime type in its report. 2024. FBI Internet Crime Complaint Center, 2024 Internet Crime Report, read 2026-10-18.

What LookValid does for this

LookValid products for Marketing
Check	What it gives you	Credits
Clean a list by domain before you send	Flags disposable domains, free providers and role mailboxes, and reports MX, SPF and DMARC. Run it on your own sending domain too. It cannot confirm that an individual mailbox exists.	1 credit per address checked
Format numbers for SMS lists	Returns the E.164, national and international formats, the country and the number type the plan assigns. It is a numbering-plan check, so it does not say whether a line is active.	1 credit per valid number
Read a creator's link page	Fetches a public link-in-bio page and returns the profile title, description and outbound links, so a partnership sheet is filled from the page itself.	3 credits per resolved page (dead or empty pages are free)
Check the domain of a link before you share it	Checks the domain of a URL against the CERT Polska Warning List and reports whether it or a parent domain is listed. A domain that is not listed has not necessarily been reviewed, since the list only holds reported domains.	1 credit per URL checked (a check that cannot run is free)

A real request and response

Run the sending domain or a subscriber address through one call and read the mail setup back. This is a real captured request and response.

POST /v1/email-domain-check

1{
2  "email": "info@example.com"
3}

Response, captured 2026-10-18

1{
2  "found": true,
3  "data": {
4    "email": "info@example.com",
5    "syntax_valid": true,
6    "domain": "example.com",
7    "mx_records": [],
8    "has_mx": false,
9    "null_mx": true,
10    "implicit_mx": false,
11    "spf": {
12      "record": "v=spf1 -all",
13      "record_count": 1,
14      "policy": "-all",
15      "valid": true,
16      "issues": []
17    },
18    "dmarc": {
19      "record": "v=DMARC1;p=reject;sp=reject;adkim=s;aspf=s",
20      "record_count": 1,
21      "policy": "reject",
22      "subdomain_policy": "reject",
23      "pct": null,
24      "rua": [],
25      "valid": true,
26      "issues": []
27    },
28    "disposable": false,
29    "free_provider": false,
30    "role_account": true,
31    "smtp_checked": false,
32    "deliverability_signal": "undeliverable",
33    "deliverability_reasons": [
34      {
35        "code": "null_mx",
36        "message": "The domain publishes a null MX record, which means it does not accept email."
37      },
38      {
39        "code": "role_account",
40        "message": "The address is a shared role mailbox such as info@ or support@, not a person."
41      }
42    ]
43  }
44}

This is one real run of Email Domain Check against a fixed public input, captured 2026-10-18. Sources: Public DNS (MX, TXT); Open disposable-email-domain and free-provider lists.

Questions

Can I use it to check my own sending domain?

Yes. Pass an address at your sending domain and read back the MX, SPF and DMARC records the check finds for it.

Does the link check say a page is trustworthy?

No. It checks the domain against one published list and reports whether it appears, with the date of the list. It does not review the page.

Can the phone check build an SMS audience?

It formats and classifies numbers by their numbering plan. Whether a line is active or who holds it is outside what the check returns.

Sources

FBI Internet Crime Complaint Center, 2024 Internet Crime Report https://www.ic3.gov/AnnualReport/Reports/2024_ic3report.pdf, read 2026-10-18

LookValid is run by Meralume Labs. It is not connected to, endorsed by or a partner of any company or product named on this page, and every product name belongs to its owner.

LookValid bills every lookup in credits from one shared balance, so one key covers each check on this page.

See Email Domain Check