I2C VS SPI
As of 4 November 2026, SPI is named by 1,559 companies and I2C by 1,515; I2C skews to companies under 200 people (53% vs 52%), SPI to companies over 1,000 (25% vs 25%).
As of 4 November 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: I2C's script and mail records show on hundreds of thousands of small sites, SPI rarely leaves a trace outside its own apps. Compare on the job-posting numbers; use the footprint for reach.
- I2C: 2–200 employees
- 53%
- SPI: 2–200 employees
- 52%
- I2C: 1,000+ employees
- 25%
- SPI: 1,000+ employees
- 25%
- Postings per company, 90 days
- 3.2 · 3.2
- Website or DNS footprint
- 0 · 0
Who chooses which
Share of each tool's companies in every segment. "Leans" marks a gap of more than two points.
| Segment | I2C | share | SPI | share | Leans |
|---|---|---|---|---|---|
| Self-employed | 28 | 2% | 32 | 2% | even |
| 2-10 employees | 188 | 12% | 189 | 12% | even |
| 11-50 employees | 259 | 17% | 257 | 16% | even |
| 51-200 employees | 352 | 23% | 358 | 23% | even |
| 201-500 employees | 202 | 13% | 214 | 14% | even |
| 501-1000 employees | 101 | 7% | 113 | 7% | even |
| 1001-5000 employees | 173 | 11% | 183 | 12% | even |
| 5001-10000 employees | 56 | 4% | 61 | 4% | even |
| 10,001+ employees | 156 | 10% | 152 | 10% | even |
| Segment | I2C | share | SPI | share | Leans |
|---|---|---|---|---|---|
| Manufacturing & industry | 749 | 49% | 752 | 48% | even |
| Technology & software | 326 | 22% | 319 | 20% | even |
| Business & finance services | 150 | 10% | 193 | 12% | SPI |
| Automotive | 53 | 3% | 53 | 3% | even |
| Commerce & trade | 46 | 3% | 41 | 3% | even |
| Utilities & infrastructure | 44 | 3% | 50 | 3% | even |
| Public, community & associations | 37 | 2% | 36 | 2% | even |
| Consumer services & leisure | 28 | 2% | 26 | 2% | even |
| Media & content | 23 | 2% | 19 | 1% | even |
| Transport, logistics & rental | 21 | 1% | 20 | 1% | even |
| Property & construction | 20 | 1% | 31 | 2% | even |
| Health care | 13 | 1% | 12 | 1% | even |
| Segment | I2C | share | SPI | share | Leans |
|---|---|---|---|---|---|
| United States | 929 | 61% | 936 | 60% | even |
| Germany | 79 | 5% | 88 | 6% | even |
| United Kingdom | 76 | 5% | 80 | 5% | even |
| India | 59 | 4% | 60 | 4% | even |
| France | 41 | 3% | 41 | 3% | even |
| Canada | 35 | 2% | 38 | 2% | even |
| Sweden | 20 | 1% | 26 | 2% | even |
| Netherlands | 19 | 1% | 20 | 1% | even |
| Poland | 17 | 1% | 20 | 1% | even |
| Spain | 15 | 1% | 21 | 1% | even |
| Italy | 15 | 1% | 13 | 1% | even |
| Switzerland | 14 | 1% | 13 | 1% | even |
| Segment | I2C | share | SPI | share | Leans |
|---|---|---|---|---|---|
| Software engineering | 3,038 | 47% | 3,015 | 46% | even |
| Engineering (non-software) | 2,552 | 39% | 2,701 | 41% | even |
| IT operations & business systems | 127 | 2% | 107 | 2% | even |
| Sales | 52 | 1% | 52 | 1% | even |
| Quality, safety & environment | 37 | 1% | 37 | 1% | even |
| Data & AI | 22 | 0% | 19 | 0% | even |
| Skilled trades and field service | 18 | 0% | 20 | 0% | even |
| Unclassified | 17 | 0% | 10 | 0% | even |
| Design & UX | 16 | 0% | 15 | 0% | even |
| Finance & accounting | 14 | 0% | 6 | 0% | even |
| Product, program & project management | 12 | 0% | 20 | 0% | even |
| Customer service & success | 7 | 0% | 16 | 0% | even |
| Marketing & communications | 3 | 0% | 2 | 0% | even |
| Research and science | 3 | 0% | 5 | 0% | even |
| Business development & strategy | 1 | 0% | – | – | outside top 12 |
| Logistics warehouse and transport | 1 | 0% | 3 | 0% | even |
| Procurement and purchasing | 1 | 0% | – | – | outside top 12 |
| Manufacturing and production | – | – | 25 | 0% | outside top 12 |
| Hospitality and food service | – | – | 23 | 0% | outside top 12 |
| Real estate and property | – | – | 13 | 0% | outside top 12 |
| Construction and civil | – | – | 3 | 0% | outside top 12 |
| Legal, compliance & risk | – | – | 1 | 0% | outside top 12 |
| Travel, leisure & events | – | – | 1 | 0% | outside top 12 |
The companies behind each column
Companies using I2C →
Companies using SPI →
iot platforms protocols ranked →
Quote the sentence with the date and the link. The numbers change daily; the link always shows the current ones.
SPI is named by 1,559 companies in job postings and I2C by 1,515; 1,751 name both. (Breaknorm, 4 November 2026, https://breaknorm.co/compare/i2c-vs-spi-bus)
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.
I2C vs SPI: questions
Which is more used, I2C or SPI?
By companies naming it in their own job postings, SPI (1,559) over I2C (1,515). By website-and-DNS footprint, SPI (0 vs 0), because its scripts and mail records sit on many small company sites.
Who chooses I2C?
53% of I2C companies have 2 to 200 employees, against 52% for SPI. 25% of I2C companies have over 1,000 employees, against 25% for SPI.
Do companies run both?
1,751 companies name both in their postings, usually I2C in marketing and SPI 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.
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with the person who owns it
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