Tools ·

Companies using inboxkit_

As of 4 November 2026, 7,476 companies run cold e-mail outbound on inboxkit, read from their sending domains in DNS; 927 added three or more sending domains in the last 30 days.

As of 4 November 2026 · refreshed daily · counts move as websites, DNS and career sites are re-read.

Cold-email outbound on it
7,476 companies
Scaling outbound now (3+ new sending domains, 30 d)
927
7,476companies show inboxkit, all sources
7,476run cold e-mail outbound on it (DNS)
927scaling outbound now: 3+ new sending domains in 30 days
0name it in their own job postings
02 — Two ways we see a tool

Where inboxkit shows up

Each population is counted on its own. We never add them up without saying so, because they answer different questions.

Website and DNS footprint0

Companies whose own pages load inboxkit's scripts or embeds, or whose domain's mail and hosting records (SPF, DKIM, MX, CNAME) point at inboxkit. From our crawl of 41.5M company websites and the DNS sweep behind it. Reach: the tool is in the building.

Job postings0

Companies whose own postings say the team works in inboxkit. Read hourly from ~70 applicant tracking systems, with the function, a quote and a date. Intent: the team that runs it is hiring.

Sending infrastructure (DNS)7,476

Companies whose cold-e-mail sending domains (look-alike domains on inboxkit's infrastructure, found in certificate logs and DNS) redirect to them. The strongest outbound signal there is: 927 of them added three or more sending domains in the last 30 days.

03 — Who uses it

Companies on inboxkit

No company names inboxkit in its job postings with enough confidence to list yet; the companies below carry it on their website or in DNS.

7,476 companies show inboxkit; 0 of them have over 1,000 employees.

Filter by country, size, team and source, open verified e-mails for the decision makers, or push new matches to your CRM every week.

Free plan: 1,000 records, no card. The first 20 are above; e-mails are verified at the mail server when you open them.

05 — Outbound layer

Who runs cold e-mail on inboxkit

The 7,476 companies whose sending domains point at inboxkit. Mostly small teams and agencies; the ones scaling right now are the buyers of data, deliverability and enrichment.

By country
companiesshare
United States
5,09368%
United Kingdom
7009%
Germany
2864%
Canada
2013%
Netherlands
1262%
France
1222%
Australia
1031%
India
921%
Spain
641%
Switzerland
471%
Poland
461%
Italy
431%
By company size
companiesshare
Self-employed
2,59835%
2-10 employees
1,93126%
11-50 employees
1,74723%
51-200 employees
77410%
201-500 employees
2163%
501-1000 employees
891%
1001-5000 employees
741%
5001-10000 employees
150%
10,001+ employees
320%
By industry
companiesshare
Technology & software
3,00140%
Business & finance services
2,54234%
Consumer services & leisure
4526%
Manufacturing & industry
3715%
Property & construction
2764%
Media & content
2423%
Commerce & trade
1472%
Hospitality & travel
1312%
Transport, logistics & rental
1051%
Public, community & associations
631%
Health care
621%
Utilities & infrastructure
621%
927 companies on inboxkit added three or more sending domains in the last 30 days.

Filter on outbound_provider and outbound_new_30d_count, open the founder or head of growth with a verified e-mail, or get every newly scaling account each morning.

Free plan: 1,000 records, no card. The first 20 are above; e-mails are verified at the mail server when you open them.

Cite this

Quote the sentence with the date and the link. The numbers change daily; the link always shows the current ones.

7,476 companies run cold e-mail outbound on inboxkit: their sending domains, read from DNS and certificate logs, point at inboxkit's infrastructure; 927 of them added three or more sending domains in the last 30 days. (Breaknorm, 4 November 2026, https://breaknorm.co/tools/inboxkit)
How we know

Read from the source, not self-reported

Every number on this page can be traced to a page we crawled or a posting we read. Full methodology →

  • Website codeScripts, tags and embeds found on the company's own pages in our crawl of 41.5M sites. A tool counts once per company.
  • DNS recordsSPF includes, DKIM selectors, MX and CNAME records of the company's domain that point at inboxkit or another vendor. Swept in cycles; dedicated mail-provider and hosting facets open once coverage passes 80% per country.
  • Job postingsRead hourly from the applicant tracking systems behind company career sites. A tool counts when the employer's own text names it as the team's system; candidate wish-lists and apply boilerplate are excluded. Confidence low, medium or high per company.
  • Sending infrastructureCold-e-mail sending domains are look-alike domains on a provider's infrastructure (DNS records, certificate logs) that redirect to the company. Absence is not evidence: only companies with a found sending domain are counted.
  • CompaniesCountry, size and industry come from the company profile we build from its website; headcount from LinkedIn where known, otherwise estimated. Job boards, portals and aggregators are kept out of lists.
FAQ

inboxkit data: questions

How many companies use inboxkit?

7,476 as of 4 November 2026: 0 carry inboxkit on their website or in their DNS records and 0 name it in their own job postings; 0 show up in both. We keep the two counts apart because they measure different things.

What does "website or DNS" mean?

Our crawler finds inboxkit's scripts, embeds and tags on the company's own pages, and our DNS sweep reads the domain's mail and hosting records (SPF includes, DKIM selectors, MX, CNAMEs) that point at inboxkit. Either one puts the company in the footprint. The sweep is still running, so this number grows week by week.

Why is the job-posting number so much smaller?

A posting only names a tool when the team that will use it is hiring and chooses to say so. That makes it a smaller but stronger signal: it tells you which team runs inboxkit, with a quote and a date. The footprint tells you reach.

How fresh is this?

Career sites are read hourly, websites are re-crawled on a rolling schedule and DNS is re-swept in cycles. The date at the top is when these counts were computed.

Can I get the list?

Yes. The first 20 are on this page; the full 7,476 with verified e-mails and a weekly feed of new inboxkit users is in the product. Counting is free.

Companies and people

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