Compare · linux unix

Linux VS POSIX_

As of 30 October 2026, POSIX is named by 103 companies and Linux by 12,080; Linux skews to companies under 200 people (55% vs 35%), POSIX to companies over 1,000 (29% vs 21%).

As of 30 October 2026 · refreshed daily · counts move as websites, DNS and career sites are re-read.

The website-and-DNS footprint is not comparable between a marketing suite and a CRM: Linux's script and mail records show on hundreds of thousands of small sites, POSIX rarely leaves a trace outside its own apps. Compare on the job-posting numbers; use the footprint for reach.

Linux: 2–200 employees
55%
POSIX: 2–200 employees
35%
Linux: 1,000+ employees
21%
POSIX: 1,000+ employees
29%
Postings per company, 90 days
5.3 · 2.1
Website or DNS footprint
0 · 0
12,080companies name Linux
103companies name POSIX
0name both
64,552 · 218postings in 90 days, Linux · POSIX
02 — Side by side

Who chooses which

Share of each tool's companies in every segment. "Leans" marks a gap of more than two points.

By company size
SegmentLinuxsharePOSIXshareLeans
Self-employed1201%––outside top 12
2-10 employees1,0098%55%Linux
11-50 employees2,71322%1616%Linux
51-200 employees2,95624%1515%Linux
201-500 employees1,67514%2019%POSIX
501-1000 employees1,0469%1717%POSIX
1001-5000 employees1,40012%1313%even
5001-10000 employees3893%66%POSIX
10,001+ employees7726%1111%POSIX
By industry
SegmentLinuxsharePOSIXshareLeans
Technology & software5,74048%4645%Linux
Business & finance services1,98216%88%Linux
Manufacturing & industry1,80415%3029%POSIX
Utilities & infrastructure3903%33%even
Consumer services & leisure3783%33%even
Public, community & associations3593%22%even
Media & content3253%44%even
Commerce & trade2782%22%even
Health care2192%11%even
Property & construction1691%––outside top 12
Transport, logistics & rental1691%11%even
Automotive1561%33%even
By country
SegmentLinuxsharePOSIXshareLeans
United States6,13151%7270%POSIX
Germany1,44212%55%Linux
United Kingdom7076%66%even
France4674%11%Linux
India3803%44%even
Canada2972%33%even
Italy2072%––outside top 12
Netherlands1912%––outside top 12
Switzerland1791%––outside top 12
Poland1721%––outside top 12
Australia1551%11%even
Austria1511%11%even
Sweden––22%outside top 12
Belgium––11%outside top 12
Bulgaria––11%outside top 12
Denmark––11%outside top 12
Postings by team (share of each tool's postings)
SegmentLinuxsharePOSIXshareLeans
Software engineering33,75237%19856%POSIX
IT operations & business systems24,78228%339%Linux
Engineering (non-software)7,4298%82%Linux
Data & AI4,1065%134%even
Customer service & success1,8532%––outside top 12
Sales1,4232%72%even
Product, program & project management8781%31%even
skilled trades and field service5501%21%even
research and science5211%––outside top 12
Quality, safety & environment2900%134%POSIX
Education & training2800%10%even
Unclassified2800%––outside top 12
logistics warehouse and transport––21%outside top 12
Business development & strategy––10%outside top 12
manufacturing and production––10%outside top 12
Cite this

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

POSIX is named by 103 companies in job postings and Linux by 12,080; 0 name both. (Breaknorm, 30 October 2026, https://breaknorm.co/compare/linux-vs-posix)
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 →

  • Job postingsRead hourly from career sites. A tool counts when the employer's own text names it as the team's system; both tools can count for one company.
  • Website and DNSScripts and embeds on the company's pages, plus SPF, DKIM, MX and CNAME records of its domain that point at the vendor.
  • SegmentsCountry, size and industry from the company profile built from its website.
  • Not a reviewNo ratings, prices or feature claims. For those, read the vendors.
FAQ

Linux vs POSIX: questions

Which is more used, Linux or POSIX?

By companies naming it in their own job postings, Linux (12,080) over POSIX (103). By website-and-DNS footprint, POSIX (0 vs 0), because its scripts and mail records sit on many small company sites.

Who chooses Linux?

55% of Linux companies have 2 to 200 employees, against 35% for POSIX. 21% of Linux companies have over 1,000 employees, against 29% for POSIX.

Do companies run both?

0 companies name both in their postings, usually Linux in marketing and POSIX in sales, or during a migration.

Where do these numbers come from?

From the employer's own text in job postings read hourly from career sites, and from scripts found on company websites in our crawl. No vendor data, no surveys.

Companies and people

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