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Lead data and prospecting

Check email domains, domain age and website contacts in FindThatLead

Check the domains of the emails you export from FindThatLead before you send, so risky, disposable and role addresses are separated from the rest.

Why the data matters in FindThatLead

A prospecting tool hands you emails found or guessed for a person at a company. Some of those sit on domains with no mail records, and some are generic role mailboxes. Sending to them without a check raises bounces on your sending domain and hides which leads actually have a reachable inbox.

What LookValid checks

ProductWhat it does hereCredits
Email Domain CheckReturns a good, risky or undeliverable signal from the domain records of each exported email. It does not contact the mail server or prove the mailbox exists. Separates role mailboxes such as info@ and free providers from named business addresses in an export.1 credit per address checked
Domain AgeReturns registration date and age for the company domain, to spot a freshly registered domain in a list.2 credits per registered domain (unregistered domains are free)
Website Contacts ScraperReads a public company site and returns the contact details it shows, to compare with the emails you exported.10 credits per domain with contacts found

Connect it in four steps

  1. Open a LookValid account, visit the dashboard and issue a key under API keys.
  2. Place the key in the LOOKVALID_API_KEY environment variable of the shell that runs the script, so the downloaded lead file stays free of credentials.
  3. Call check_findthatlead_email with the email of each row of the CSV: skip a row on found:false, and let an error stop the run with its code and fix printed.
  4. Add email_signal, role_mailbox and has_mx as columns in the checked copy and keep only the rows whose signal is good. FindThatLead removes processed lists from its Uploads area after 30 days, so keep your own copy of the CSV.

A Python script that reads a CSV of leads downloaded from FindThatLead, for example a Prospector list, one row at a time, and writes a checked copy. The call is POST https://YOUR_API_HOST/v1/email-domain-check and costs 1 credit per address checked.

check_findthatlead_email.py
import json
import os
import urllib.error
import urllib.request
​
API_URL = "https://YOUR_API_HOST/v1/email-domain-check"
​
​
def check_findthatlead_email(value):
    request = urllib.request.Request(
        API_URL,
        data=json.dumps({
            "email": value,
        }).encode(),
        headers={
            "Authorization": "Bearer " + os.environ["LOOKVALID_API_KEY"],
            "Content-Type": "application/json",
        },
        method="POST",
    )
    try:
        with urllib.request.urlopen(request, timeout=30) as response:
            result = json.load(response)
    except urllib.error.HTTPError as error:
        failure = json.load(error)["error"]
        raise RuntimeError(failure["code"] + ": " + failure["fix"])
    if not result["found"]:
        return None
    return {
        "email_signal": result.get("data", {}).get("deliverability_signal"),
        "role_mailbox": result.get("data", {}).get("role_account"),
        "has_mx": result.get("data", {}).get("has_mx"),
    }
Response fieldGoes into
data.deliverability_signalemail_signal
data.role_accountrole_mailbox
data.has_mxhas_mx

The recipe returns nothing when the lookup finds nothing, which costs no credits for this product, and stops with the error code and fix on a failed request.

Without code

Without code, use an automation platform that has a generic HTTP request step and no dedicated app. Paste or import the CSV you downloaded from FindThatLead into a sheet, and for each new row post the email to the LookValid email-domain-check endpoint and store the signal in the next column.

REST and MCPOne shared credit balance

Questions

What does checking an export cost?

One email-domain-check lookup per row, at the credit rate on the pricing page.

Is a good signal the same as a working inbox?

No. A good signal means the domain accepts mail and is not disposable. It cannot tell if the person behind the address exists.

Where do I keep the key?

In the LOOKVALID_API_KEY variable of the process that runs the script, never in the downloaded file.

FindThatLead has its own Verify tool. Why add this?

FindThatLead describes its Verify as checking format, type, server status and email status, with green, yellow and grey scores. A LookValid pass is a second, separate reading of the domain records, useful as a cross-check before you send.

Sources

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 the same key works for each check above.

See Email Domain Check