List Cleaning verifies whether the addresses on your list can actually receive mail, so invalid contacts get caught before a campaign reaches them. Fewer bounces means a healthier sender reputation, and a healthier sender reputation means more of your mail reaching the inbox. $10/month plus $0.003 per validation — you pay for what you verify.
Most lists decay quietly. People change jobs, abandon addresses, and mistype signups — and you find out when your bounce rate spikes and your domain reputation is already damaged.
Each address you verify comes back with a status, so you know which contacts are safe to send to and which will bounce. Invalid addresses are the ones that damage your sender reputation. Unknown addresses are the ones a mail server would not confirm either way — useful to know before you decide whether to keep sending to them.
Run a bulk verification across your existing contacts — all of them, only the ones never cleaned before, or a subset filtered by status. Then switch on auto-cleaning so new contacts are verified as they arrive and the problem does not rebuild itself. Cleaning runs as a background job, so large lists do not hold up your account.
List Cleaning is $10 per month plus $0.003 per validation, drawn from pay-as-you-go credits. A one-off clean of a 50,000-contact list costs $150 in validations; verifying a few hundred new signups a month costs a few dollars. You can export the verification results to CSV at any point, filtered by time range, if you want the data outside SendX.
It runs against the contacts already in your account — there is no file to upload and no list to re-import afterwards.
Switch List Cleaning on from the Addons area of your account. Once enabled it gives you three views — an overview, settings for automatic cleaning, and an analytics tab showing what cleaning has done for you over the last 30 days. Because it works on the contacts already in SendX, there is nothing to export from your account and re-upload somewhere else.
Start a clean and pick the scope — every contact in the account, only the ones that have never been cleaned, or a filtered subset by status. Since you pay per validation, cleaning only uncleaned contacts is usually the sensible default once you have done an initial pass. The job runs in the background while you carry on working.
Results come back split into valid, invalid, and unknown, with the proportion of your list in each. Invalid addresses are the ones to remove — they are what drives your bounce rate. If you want the underlying data outside SendX, export the verification results to CSV for whatever time range you need.
Switch List Cleaning on from the Addons area of your account. Once enabled it gives you three views — an overview, settings for automatic cleaning, and an analytics tab showing what cleaning has done for you over the last 30 days. Because it works on the contacts already in SendX, there is nothing to export from your account and re-upload somewhere else.
Start a clean and pick the scope — every contact in the account, only the ones that have never been cleaned, or a filtered subset by status. Since you pay per validation, cleaning only uncleaned contacts is usually the sensible default once you have done an initial pass. The job runs in the background while you carry on working.
Results come back split into valid, invalid, and unknown, with the proportion of your list in each. Invalid addresses are the ones to remove — they are what drives your bounce rate. If you want the underlying data outside SendX, export the verification results to CSV for whatever time range you need.
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$10 per month, plus $0.003 per address validated. The addon fee and the per-address charge are separate, and validations are drawn from pay-as-you-go credits. There is no annual verification commitment — you buy credits and each address checked draws one down. As a rough guide, a one-off clean of a 50,000-contact list works out at $150 in validations, while verifying a few hundred new signups each month costs a few dollars.
Valid means safe to send. Invalid means confirmed dead. Unknown means the server would not say either way. In more detail: a valid address was confirmed as able to receive mail. An invalid one was confirmed non-existent or malformed — these cause the hard bounces that damage your sender reputation, and they are the ones to remove. Unknown results are common with catch-all domains, which accept anything at the server level and reveal nothing. Unknown addresses are not necessarily bad, but they carry more risk than confirmed valid ones, so it is worth judging them on engagement history before you keep mailing them.
Yes. Auto-cleaning verifies new contacts as they are added to your account, so a list you have cleaned once does not slowly refill with invalid addresses from form signups, imports, and API calls. Most people run one bulk clean across their existing contacts to deal with the backlog, then leave auto-cleaning on to keep it that way. Each automatically verified address consumes a credit in the same way a bulk one does.
No, and be wary of any provider that claims otherwise. No email hygiene product can guarantee 100% cleaning or threat removal — verification identifies known invalid addresses and known threats, and some mail servers deliberately refuse to confirm whether an address exists, which is why the unknown status exists. What list cleaning reliably does is remove the confirmed-bad addresses that drive hard bounces, which is where the damage to your sender reputation comes from.
List Cleaning answers whether an address is real and able to receive mail. Threat Checks is a separate addon that catches what plain verification cannot — spam traps, honeypots, complainers, disposable domains, and other risky addresses that may be perfectly valid but are dangerous to send to. It flags each contact as clean, or as a reputation, fraud, delivery, or conversion risk. The two solve different problems and are priced separately: List Cleaning is $10/month plus $0.003 per validation, Threat Checks is $10/month plus $0.005 per check. Senders working with older or bought-in lists often run both.
Every few months for most senders. If auto-cleaning is on, new contacts are already handled as they arrive, so a periodic pass over older contacts is what remains. Email lists decay steadily — people change jobs and abandon addresses — so a list left untouched for a year will have accumulated invalid contacts even if nothing was added. A bulk clean every few months is a reasonable rhythm, and worth doing sooner if you see your bounce rate climbing or you are about to mail a segment you have not touched in a long time.
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Enable List Cleaning from your addons page and run a verification across your existing contacts. $10/month plus $0.003 per address — you pay for what you check.
