Chromium
Description
Most people have never used Chromium by name, but almost everyone who uses the internet in 2026 depends on it. Google Chrome is Chromium with proprietary components on top of it. Microsoft Edge was rebuilt on Chromium in 2020. Opera, Brave, Vivaldi, Samsung Internet, CentBrowser, Epic Privacy Browser, Waterfox’s new Android builds — all Chromium underneath. The browser that a developer downloads to test a web app, the kiosk at the airport gate and the head unit in a new car are almost certainly running some derivative of this same codebase. It began shipping on September 2, 2008, the same day Chrome first betaed and has been in continuous development ever since.
Chromium is the name of the open-source project and the name of the browser that project produces. Google began the project when it launched Chrome, releasing most of Chrome’s source code under the BSD license so that anyone could build it, modify it and redistribute it. The resulting browser — plain Chromium, compiled straight from the source tree — is a fully functional browser that looks almost exactly like Chrome, missing a set of specific things that Google kept proprietary. Those absences are not flaws, they’re the point. Chromium is the basis that other browsers build from, and a browser in its own right for the users who specifically want what Chrome is without what Google added.
The name is based on a simple logic: chromium is the metal used to make chrome plating. Chrome gets its shine from chromium underneath.
WHO USES CHROMIUM
Three groups use the Chromium browser directly instead of through Chrome or another derivative.
Developers constitute the majority of the user base. Web developers use Chromium to test pages against the browser engine that processes the majority of the world’s web traffic without having to run Google’s services in the background. The DevTools are the same as Chrome’s — breakpoints, network inspection, performance profiling, the console — and any behavior a developer sees in Chromium will look the same in Chrome. Testing against Chromium means testing against the engine without the confounding variables of Google’s other layers.
Linux users find Chromium packaged in their distribution’s software repositories. Debian, Ubuntu, Arch Linux, Fedora, and most other major distributions install Chromium as the available Chromium-based browser, as Google does not officially support Chrome on all variants of Linux, and because the open-source build is available to be packaged and redistributed by the distribution. Installing Chrome on Linux requires fetching Google’s repository; installing Chromium on most Linux systems is a package manager command. For many Linux users, Chromium is simply the practical option.
Privacy-conscious users who want the rendering engine of Chromium without the sync, telemetry, and service hooks of Google use the plain browser precisely because it lacks these components. Some go even further with Ungoogled Chromium, a third-party project that strips away even more of the remaining Google integrations, but standard Chromium already strips out Google account sync, Safe Browsing data upload, and the RLZ identifier that Chrome sends to correlate usage.
RELATES TO GOOGLE CHROME
Understanding what Chromium is requires understanding exactly what Chrome adds on top of it.
Both are using the same core engines: Blink for rendering and V8 for JavaScript. They both use the same tab isolation architecture, the same extension framework, the same developer tools, the same URL bar behavior. A page that loads a certain way in Chromium loads the same way in Chrome because they share the same rendering code.
The differences are a specific list of proprietary additions that Google owns and does not open source. Chrome comes with Widevine, Google’s Digital Rights Management module, which streaming services such as Netflix and Disney+ use to play their content. Without Widevine, Chromium is unable to play DRM-protected video at the quality levels required by those services. Chrome comes with H.264, AAC and MP3 codecs under license — formats that Chromium does not come with because the patents on them prevent open source distribution. Chrome comes with Google Sync, which links bookmark, password, history and settings storage to a Google account. Chrome has Safe Browsing Enhanced Protection, which sends information about URLs to Google’s servers in order to check for threats in real time. Chrome updates itself automatically in the background without any interaction from the user.
Chromium has none of those by default. Most Linux distributions package a version of Chromium that adds the open media codecs back in (VP8, VP9, Opus and increasingly AV1), which handles most video playback on non-DRM content. Widevine has to be installed separately from a Chrome binary. Safe Browsing exists in Chromium but in a reduced form which does not send URL data back to Google. Auto-update is not available — Chromium users on Linux receive updates from their distribution’s package manager; Windows and macOS users must manage updates themselves or use a third-party tool.
THE BLINK ENGINE AND V8
Chrome was released in 2008 with WebKit being the rendering engine. WebKit was Apple’s open-source engine, which is also used in Safari, and Google thought it was the obvious place to start. For the first few years this worked well enough, but Chrome’s novel multi-process architecture — each tab running in a separate process — required engine changes that diverged more and more from what Apple wanted for Safari. The two teams began heading in opposite directions.
In April 2013, Google forked WebKit and called the new engine Blink. From then on, Chromium and Chrome ran on code that Google controlled and was free to modify. Blink is responsible for parsing the content of the web page (html and css), the layout of the web page, and the compositing of what gets displayed on the screen. V8 handles JavaScript — it compiles JavaScript to native machine code instead of interpreting it line by line, which was one of the original reasons Chrome felt dramatically faster than Firefox and Internet Explorer when it launched.
Blink became the engine around which the larger browser industry coalesced. Microsoft’s decision in 2020 to rebuild Edge on Chromium, instead of continuing to use its own EdgeHTML engine, meant that the only major browsers not using Blink in 2025 are Firefox (Gecko) and Safari (WebKit, which itself shares ancestry with Blink, via their shared origin in Konqueror).
MULTI-PROCESS ARCHITECTURE
When Chrome was launched in 2008, the browser was accompanied by a 38-page comic book that Google mailed to journalists. One of its key concepts was multi-process tab isolation: each tab was a separate operating system process. If a tab crashed, it crashed alone. The remainder of the browser continued to run.
This was unusual at the time. Most browsers ran everything in a single process, which meant that a crashed page could take down the whole browser session. Chromium’s architecture put tabs in their own processes, then went further – isolating the rendering engine from the browser process itself, and sandboxing the renderer so that even if a webpage ran malicious code, that code couldn’t reach the rest of the system without escaping the sandbox.
The architecture is expensive in terms of memory. Each process has its own overhead, and that is why Chrome and Chromium have a reputation for consuming more RAM than Firefox. The trade-off is stability and security: one naughty tab can’t touch another.
By 2025, this design was influential in every major browser. Firefox switched to process isolation over a period of several years. Safari re-organised around similar principles. The architecture that Chromium pioneered in 2008 is now the standard.
EXTENSIONS
Chromium supports the same extensions as Chrome, which are available from the Chrome Web Store. The entire catalog of more than 150,000 extensions works in Chromium because the extension API is the same. Password managers, ad blockers, developer tools, any other Chrome extension install and run the same.
In June 2025, Google finished the manifest V2 to manifest V3 migration in the Chrome Web Store, removing older extensions and finishing a migration that had been in progress since 2022. This change is inherited by chromium. Extensions that relied on the older API’s broader access to web requests — including many ad blockers and content filters — had to rewrite for the new API or disappear from the store. The change was met with sustained criticism by browser makers and security researchers who said the new API undermined ad blocking capabilities. Other Chromium-based browsers were more varied in their response: Some continued to have separate availability for Manifest V2 extensions even after Chrome removed them.
Developers are able to sideload extensions in Chromium without the signed package requirement that Chrome imposes.
DEVELOPER TOOLS
The DevTools panel in Chromium is the same as Chrome’s and is one of the most popular browser development environments in existence. Pressing F12 opens a full-panel debugger with tools for inspecting elements and styles live, stepping through JavaScript code, monitoring network requests, including timing and headers, profiling JavaScript and rendering performance, auditing pages with Lighthouse, simulating devices and screen sizes, and inspecting storage, including localStorage, cookies, and IndexedDB.
Because the Chromium DevTools protocol (CDP) provides programmatic access to the browser, Chromium is the browser that most web automation tools target. Puppeteer, Playwright and Selenium all support Chromium. CI/CD pipelines that require browser testing require the use of Chromium or the special Chrome for Testing distribution that Google maintains for reproducible testing environments.
UNGOOGLED CHROMIUM
Ungoogled Chromium is a community-maintained project which takes the standard Chromium and strips away additional Google integrations that persist in the base code even after removing Google’s proprietary additions. The project, hosted on GitHub and maintained primarily by a contributor known as Eloston, along with others, patches out requests to Google domains, removes the safe browsing integration entirely, disables background service workers that communicate with Google servers, and strips the remaining update-checking code.
Installing Ungoogled Chromium requires more manual installation than normal Chromium — the Chrome Web Store does not work by default because the installation mechanism checks for Google’s signature; users install a separate extension to re-enable it. Widevine installation requires unpacking files from a chrome binary. The result is a browser with the rendering fidelity of Chromium, and no remaining Google network communication by default. Ungoogled Chromium is available for Windows, macOS, Linux and Android via the project’s GitHub releases page and various distribution-specific package repositories.
ELECTRON AND EMBEDded APPLiactions
Chromium is the engine within Electron, a framework for creating desktop applications with web technologies. Slack, Visual Studio Code, Discord, Figma’s desktop app, Obsidian, and a plethora of other popular desktop applications bundle up a Chromium-based renderer with their JavaScript application logic. When one of those apps pops up a window, it’s using a stripped Chromium render process to do it.
This makes Chromium simultaneously both a browser and the rendering engine for a significant portion of the software that people use every day without thinking of it as a browser. The same Blink engine used to parse a webpage in Chrome parses the interface in VS Code.
CHROMIUM OS
Chromium OS is the open source version of ChromeOS, Google’s operating system for Chromebook hardware. ChromeOS is to Chromium OS as Chrome is to Chromium — Google takes the open source project and adds proprietary services, the Play Store and hardware certification on top. Chromium OS itself runs on standard PC hardware as a bootable image, mostly for developers and experimenters. The two projects share source code but ChromeOS is the consumer product and Chromium OS is the underlying open source base.
