Tools · ai coding assistants

Companies using Codex_

As of 4 November 2026, 2,265 companies name Codex in their own job postings; it leaves no trace on websites or in DNS.

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

Largest market
–
Companies with 51+ staff
–
Top industry
–
Team that names it most
Software engineering · 3,012 postings
Hiring on it, last 30 days
1,607 companies
Most often alongside
Claude Code · 2,055 companies
2,265companies show Codex, all sources
0on their website or in DNS records
2,265name it in their own job postings
5,911postings naming Codex, last 90 days
02 — Two ways we see a tool

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

Job postings2,265

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

Both0

Companies in the footprint whose postings also name Codex. The rest of the posting population (2,265) runs Codex without a public trace on the site or in DNS, which is where job data earns its place.

03 — Who uses it

Companies on Codex

Companies with 201+ employees and high-confidence evidence in their own postings; job boards and portals left out.

2,265 companies show Codex; 0 of them have over 1,000 employees.

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06 — Job-posting evidence

Who runs Codex inside the company

The 2,265 companies whose postings name Codex: by country, size and the function of the role. The second number in the function table is companies.

Postings by function
postings · companies
Software engineering
3,012 · 1,294
Data & AI
1,606 · 834
IT operations & business systems
419 · 166
Product, program & project management
357 · 207
Engineering (non-software)
184 · 92
Sales
165 · 97
Marketing & communications
142 · 93
Design & UX
121 · 86
Finance & accounting
95 · 55
General management & consulting
58 · 35
Posting companies by country
companiesshare
United States
1,44764%
United Kingdom
1517%
Germany
1376%
Canada
462%
France
422%
Sweden
301%
India
241%
Brazil
231%
Japan
231%
Netherlands
231%
Poland
201%
Switzerland
181%
Posting companies by size
companiesshare
Self-employed
1256%
2-10 employees
25611%
11-50 employees
36916%
51-200 employees
47721%
201-500 employees
30513%
501-1000 employees
2109%
1001-5000 employees
29113%
5001-10000 employees
763%
10,001+ employees
1567%
Hiring on it right now
postings
Postings, last 30 days
4,288
Postings, last 90 days
5,911
All open postings
7,213

1,607 companies opened a role that names Codex in the last 30 days. A hiring team that names its tools is the moment to write to the person who owns the stack.

07 — Named alongside

What Codex teams also ask for

Tools named in the same postings as Codex. Office software is left out.

08 — ai coding assistants

Codex against the rest of its category

Ranked by companies naming each tool in postings. Whole category →

Cite this

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

2,265 companies name Codex in their own job postings; it leaves no trace on websites or in DNS, so the posting layer is the whole picture. (Breaknorm, 4 November 2026, https://breaknorm.co/tools/codex)
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 Codex 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

Codex data: questions

How many companies use Codex?

2,265 as of 4 November 2026: 0 carry Codex on their website or in their DNS records and 2,265 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 Codex'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 Codex. 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 Codex, 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 2,265 with verified e-mails and a weekly feed of new Codex users is in the product. Counting is free.

Companies and people

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