New Playbook: Cold Email Infrastructure Setup Guide

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verified_user Bulk Email Verification

Bulk Email Verification That Costs About $3 per 100,000 Addresses

Upload a CSV, an XLSX or a Google Sheet. Every address gets a live SMTP check against its own mail server, and the file comes back split into deliverable, undeliverable, catch-all and risky. One credit per address, 75,000 credits for $9.99 a month.

Verify a list free See how it works
bolt 1 credit per address

Used by 1,000+ sales, recruiting and marketing teams

Regent Peak Myoprocess Lumina Global

Three ways to run a bulk check

Upload a file, connect the tool your list already lives in, or send the whole array through the API. Same verification underneath.

verified_user

Upload a file

CSV, XLSX or Google Sheet with an email column. Every other column comes back untouched, with a status added.

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stacks

Verify where the list lives

Google Sheets, HubSpot, Zapier, Make and n8n run the check on a schedule, so the list is clean the night before the send.

Connect a tool
terminal

Send it through the API

POST /email/verifyBulkEmail with an array of addresses and get one JSON array back, built into your own pipeline.

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What every address in the file goes through

A bulk verifier that only checks syntax and MX records returns a clean-looking file and leaves the expensive bounces in it. Every row you upload runs the full sequence, which is why the deliverable segment is the one you can actually send to.

01
spellcheck

Syntax and duplicates

Malformed rows and repeats are removed before any network work starts, and duplicates cost you nothing.

02
dns

DNS and MX lookup

Domains with no mail server are marked undeliverable immediately, without a wasted SMTP attempt.

03
handshake

SMTP handshake per address

Each mailbox is checked with its own mail server, in parallel, without a message being delivered.

04
verified

Four-way segmented file

Deliverable, undeliverable, catch-all and risky, each downloadable on its own.

From upload to clean file

The same three steps whether the list is 500 rows or 500,000, and nothing to configure.

1

Upload the list

Drop the file in. Large files keep processing if you close the tab.

2

Parallel verification

Addresses are checked independently and strict servers are paced, so the job finishes rather than getting blocked.

3

Download by status

Deliverable for sending, catch-all to decide on, undeliverable and risky to suppress.

What bulk verification costs here

1
Credit per address
$10
To verify 100,000 addresses on Growth
100
Free addresses a day, no card
4
Segments in the file you download
Service Mailsfinder ZeroBounce Emailable Kickbox
Entry price $9.99/mo, 75,000 credits $39 for 2,000 (pay as you go) $38 for 5,000 $5 for 500
Verify 100,000 addresses About $10 (within the Growth plan) Pay-as-you-go tiers $420 pay as you go $800
Free tier 100 a day 100 a month 250 once 100 once
Find missing addresses too Yes, 3 credits per found address Separate product No No
Upload formats CSV, XLSX, Google Sheets, API CSV, API CSV, API CSV, API

Who runs bulk checks here

groups

Cold email teams

Re-verify every list the night before it goes into Instantly or Smartlead, so the sending domain stays off the throttle list.

campaign

Marketers with an ESP list

Clean the newsletter list monthly and keep the bounce rate under the 2 percent line inbox providers watch.

rocket_launch

Agencies

Verify each client list on intake and before every launch, and pass the cost through at a few dollars per hundred thousand.

business_center

Data and RevOps teams

Run the CRM through on a schedule so dead contacts are flagged before sales works them.

Frequently asked questions

How much does it cost to verify a bulk list? expand_more
One credit per address, so 100,000 addresses is 100,000 credits. That is more than a Starter cycle holds, so a run that size sits on Growth at $19.99 for 200,000 credits, about $10 for the file. Agency brings it to about $8.17 and Lifetime draws on the 1,000,000 credit pool for $249 one time. There is no separate bulk price and no minimum pack, which is the main difference from the pay-as-you-go verifiers that charge $150 to $800 for the same list.
What file formats can I upload? expand_more
CSV, XLSX or a Google Sheet. The file comes back with every column you uploaded, untouched, plus a status column. You can also download each segment on its own, so the deliverable list goes straight into your sending tool without a spreadsheet detour.
How long does a large list take? expand_more
Addresses are checked in parallel against each domain's own mail server, so most lists in the tens of thousands finish within the hour. Very large lists at strict providers take longer, because those servers rate-limit lookups and we pace rather than get blocked. The job keeps running if you close the tab.
What happens to catch-all addresses in a bulk run? expand_more
They come back in their own segment, flagged rather than deleted. A catch-all domain accepts every address, so no verifier can confirm one mailbox on it. Sending to that segment is a judgement call, and having it separated means you can make it deliberately instead of by accident.
Do credits expire? expand_more
Monthly credits refresh each cycle. Lifetime credits sit in a pool that does not expire. Either way the same balance covers bulk verification, single checks, the finder and the API, so an unused month is not money burned on a product you did not need.

Upload the list. Get it back sorted.

Start with 100 free verifications a day, no card. Run the whole list when you are ready: 75,000 credits for $9.99 a month.

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