Company lists · Data refreshed September 2026
Top 25 Open source software companies worldwide
RevenueBase identified 359 open source software companies worldwide as of September 2026 and tracks 31,294 professional contacts across them, including 12,587 with verified work emails and 6,399 with mobile numbers. The United States is the largest market and Paris the largest hub.
This list covers open source software companies worldwide, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 5, 2026. Country and city lists for open source software companies follow the table.
Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.
The 25 largest open source software companies worldwide
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 24,404 contacts → | ||||
Strong evidence “Red Hat is the world’s leading provider of enterprise open source solutions, using a community-powered approach to deliver high-performing Linux, hybrid cloud, edge, and…” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 2 | 1,512 contacts → | ||||
Strong evidence “The Apache Software Foundation (ASF) is the global home for open source software, powering some of the world’s most ubiquitous software projects including Apache Airflow, Apache…” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 3 | 843 contacts → | ||||
Partial evidence “The Linux Foundation is the organization of choice for the world's top developers and companies to build ecosystems that accelerate open technology development and commercial…” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 4 | 669 contacts → | ||||
Strong evidence “Webkul is one of the largest self-created open-source marketplaces in the world.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 5 | 210 contacts → | ||||
Strong evidence “Keen & Able Computers Pvt Ltd was established in 1996 as Open Source movement was just beginning to take shape.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 6 | 138 contacts → | ||||
Strong evidence “Notre Mission est depuis 20 ans, d’inventer et de développer les Logiciels Libres et Open Source éthiques (ce que nous appelons la « GoodTech ») pour participer à changer le Monde…” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 7 | 91 contacts → | ||||
Strong evidence “Frappe creates 100% open source software to help businesses grow sustainably.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 8 | 78 contacts → | ||||
Strong evidence “B1 Systems GmbH is a provider of Linux/Open Source consulting, training, development & support services.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 9 | 75 contacts → | ||||
Partial evidence “Zestbrains pvt ltd is a Leading software development company based in India catering to the enterprise solutions worldwide.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 10 | 66 contacts → | ||||
Partial evidence “Savoir-faire Linux® is an outstanding team of 50 Free Software consultants based in Montreal and Rennes.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 11 | 45 contacts → | ||||
Strong evidence “Quansight catalyzes sustainable innovation by connecting enterprise needs with community driven open source.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 12 | 40 contacts → | ||||
Indirect evidence “We help developers and company create fast, resource-efficient, secure infrastructure applications, targeting a wide range of deployment platform: from cloud to IoT, through…” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 13 | 38 contacts → | ||||
Indirect evidence “Der Anspruch der synyx GmbH & Co.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 14 | 33 contacts → | ||||
Strong evidence “Lyra Infosystems is a trusted leader in enterprise open source solutions, dedicated to empowering businesses worldwide to thrive in today's dynamic digital landscape.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 15 | 28 contacts → | ||||
Partial evidence “Vishwayon Software Private Limited is an OpenSource global IT Services company that provides customized business solutions, using the state of the art development tools available…” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 16 | 26 contacts → | ||||
Strong evidence “As an Open Source Specialist Solution provider, Silicon attunes your business to the changing technological scenarios; thereby making you outrace the competition.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 17 | 26 contacts → | ||||
Indirect evidence “Como empresa líder em consultoria, serviços e soluções baseadas na plataforma Linux, oferecemos um vasto conjunto de programas integrados, gratuitos e de alta qualidade técnica…” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 18 | 22 contacts → | ||||
Indirect evidence “Enterprise support for your entire stack powered by a self-hosted AI agent that runs entirely inside your perimeter, with human experts one escalation away.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 19 | 18 contacts → | ||||
Strong evidence “Die K&K Software AG aus Gerolzhofen existiert seit dem Jahr und ist in den Bereichen Open Source ERP (ERPNext), Softwareentwicklung, Internetanwendungen und Netzwerkbetreuung…” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 20 | 16 contacts → | ||||
Partial evidence “The core mission of the Apereo Foundation is to assist and facilitate educational organizations which collaborate to foster, develop, and sustain open technologies and innovation…” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 21 | 16 contacts → | ||||
Strong evidence “Wij zijn specialisten op het gebied van softwareontwikkeling met open source technologie.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 22 | 16 contacts → | ||||
Strong evidence “atReal is a Free Software company focused on companies and public bodies open-source softwares.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 23 | 16 contacts → | ||||
Indirect evidence “Jambu Tecnologia is a project company.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 24 | 16 contacts → | ||||
Strong evidence “Welcome to OSMO Welcome to OSMO, the only IT consulting company in Central India providing fully FOSS (free and open source software) solutions!” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
| 25 | 15 contacts → | ||||
Strong evidence “Loco (short for Loohuis Consulting) is a company that is specialised in training, consultancy, hosting and software development revolving around Free and Open Source Software.” Source: RevenueBase Database · checked Sep 5, 2026Thanks. The Data Team will review it. | |||||
RevenueBase Smart Search
RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: open source software companies. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.
- Strong evidence
- The company's own public description of its business names open source software companies.
- Partial evidence
- Its own public description names part of open source software companies, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name open source software companies. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.
RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.
Showing 25 of 359 open source software companies worldwide
See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 12,587 reachable decision-makers.
Free signup · no credit card
Open source software companies worldwide at a glance
As of Sep 5, 2026Companies by employee count
How this list was built
Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among open source software companies, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.
- Source
- The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
- Coverage
- 7 countries, largest first: the United States, India, France, Brazil, Germany, the Netherlands, Canada. Country and city lists for open source software companies are linked below.
- What qualifies
- Companies worldwide whose own description of what they do matches “open source software companies”. Matching reads each company's description, not its industry code or its name.
- RevenueBase Smart Search
- RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names open source software companies), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
- What we exclude
- Companies whose own description does not clearly place them among open source software companies, and records with no verified work email.
- Match quality
- In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
- Ranking
- Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
- Verification
- Every listed company carries at least one verified work email, 12,587 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
- Refresh
- This page's figures were pulled from the company graph between September 5, 2026 and September 14, 2026. Lists refresh periodically as the graph is re-checked.
- Corrections
- Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.
Open source software companies by location
7 lists · largest firstEvery Open source software companies list RevenueBase publishes, by country and city. Counts are matching companies in each list as of its own refresh date.
Countries
- Open source software companies based in the United States101
- Open source software companies based in India67
- Open source software companies based in France60
- Open source software companies based in Brazil39
- Open source software companies based in Germany33
- Open source software companies based in the Netherlands30
- Open source software companies based in Canada29
Frequently asked
What is RevenueBase Smart Search?
RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names open source software companies, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.
How many open source software companies are there worldwide?
RevenueBase identified 359 open source software companies worldwide as of September 2026, matched on each company's own description of what it does rather than its industry code.
What is the largest company on this list?
RED HAT, headquartered in Raleigh, tops this list with the largest team on record.
Which country has the most open source software companies?
The United States leads with 101 companies, followed by India (67) and France (60). Every open source software companies list by country and city is linked on this page.
Which city has the most open source software companies?
Paris leads with 17 headquartered companies, followed by Berlin (11) and Montreal (9).
How do I get contact information for these companies?
A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 12,587 verified decision-maker contacts tracked across these 359 companies.
How current is this list?
The list refreshes periodically as the company graph is re-checked. This page's figures were pulled from the company graph between September 5, 2026 and September 14, 2026.
Ready to reach these companies? Verified emails and direct dials for all 359 open source software companies worldwide. Start with a free account, no credit card.
Download this list →Related lists
Browse the directory
About this data
RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.