BlinkGTK for Windows — Getting started

BlinkGTK for Windows lets you use Chromium's rendering engine (Blink) as a GTK4 widget, from C.
Unpack the ZIP and run bin\blinkgtk_browser.exe and it works at once (no administrator rights needed).
The API is nearly the same as the Linux version, so you can use the same code on both operating systems (the differences are collected in "Differences from the Linux version" below).

This page describes v1.2.6-build4 (Chromium 157.0.8103.38). On Windows 11 Pro (build 26300), we built it and checked the API, rendering and display paths on 2026-11-06. The final package check also verified unpacking and running the ZIP.

Contents: Who it is for / Run it / Check that it works / Requirements / Embedding it in your app / Upgrading from an earlier version / Differences from the Linux version / The experimental GPU path / If something goes wrong

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Who it is for

• You want to embed the same rendering engine as Chromium in a GTK4 app. BlinkGTK works as a GtkWidget and is driven by a C API.

• You are considering moving from WebView2, CEF or Electron. WebView2 is a Windows-only component (Win32, WinUI, WPF and similar), so the code is not shared with Linux. CEF has C and C++ APIs and also runs on Linux, and Electron is a framework for JavaScript apps. What is different about BlinkGTK is that you can use it from C as a GTK4 widget. It is an option when you write a GTK4 app in C and want to use the same code on Linux and Windows. It is not a drop-in replacement for an existing app.

• You are considering moving from WebKitGTK. BlinkGTK has APIs with names similar to WebKitGTK's. We have not checked compatibility down to the fine details of behavior. The names correspond as follows.

  Purpose	WebKitGTK	BlinkGTK
  Create a view	webkit_web_view_new()	blink_web_view_new()
  Load a URL	webkit_web_view_load_uri()	blink_web_view_load_uri()
  Load an HTML string	webkit_web_view_load_html()	blink_web_view_load_html()
  Loading notification	load-changed signal	a load-changed signal with the same name. The order of the values differs (see the note below)

  Note: do not reuse the numeric values of load-changed. In BlinkGTK, BLINK_LOAD_STARTED=0, BLINK_LOAD_COMMITTED=1, BLINK_LOAD_FINISHED=2 and BLINK_LOAD_REDIRECTED=3 (BlinkLoadEvent in the header blink_gtk.h). In WebKitGTK, REDIRECTED is 1 and COMMITTED and FINISHED are each one higher, so reusing the numbers gives wrong results. Always compare with the BLINK_LOAD_* names. BLINK_LOAD_REDIRECTED is reserved and is not emitted at present.

• You want to try Japanese vertical text and typesetting. There is an experimental adjustment for vertical text (see Differences from the Linux version). In this version on Windows, hanging punctuation (typesetting that lets punctuation hang past the end of a line) and one-line warichu (inline cutting notes: small notes set in two lines inside a line) work. Warichu that spans lines does not exist yet, even in the Linux version.

What you need depends on what you want to do.

You want to	You need	Read
Just try it	Unpack the portable ZIP. No build environment needed	Run it
Embed it in your app	The devel ZIP and Visual Studio Build Tools (a C++ compiler). If you have none, start from installing it	the embedding section below, and section 0 of the bundled docs\building-with-blinkgtk-en.md
Build Chromium itself	Usually not needed. Use the released ZIPs (building it takes a long time and a lot of disk)	—

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Run it

1. Download and unpack

Get the ZIP files from the v1.2.6-build4-windows release of blinkgtk-dist.

File	Use
blinkgtk-1.2.6-build4-windows-x64.zip	To run it (portable). Start with this one
blinkgtk-devel-1.2.6-build4-windows-x64.zip	To embed it (headers and libraries; see Embedding it in your app)
SHA256SUMS	To check the ZIPs. Compare it with the output of certutil -hashfile <ZIP> SHA256

Unpack the portable ZIP anywhere. It includes the GTK4 and VC++ runtime DLLs, so there is nothing else to install. There is no installer (MSI) yet.

Unpacking gives three folders: bin (the executables and DLLs), docs (documentation) and share (GTK4 data), plus the license files (LICENSE.chromium, LICENSE.blinkgtk and THIRD_PARTY_NOTICES.html).

2. A warning may appear the first time

This package is not code-signed. If you download it with a browser and run it, Microsoft Defender SmartScreen may show a warning. Follow the prompt to continue (in general, choose "More info" in the warning and then "Run anyway"; we have not captured the actual screen for this release).

The first start right after unpacking can be slow. Microsoft Defender scans the newly written files (there are about 590 DLLs). From the second start on, it is fast. In our check (Intel Core i5-1140G7, default Defender settings, 2026-10-23), the first start right after unpacking took about 11 seconds until the window appeared, and the later starts took about 0.9 seconds. The time varies with the machine and the Defender settings. It will start if you wait, so please wait.

If you use a Windows 11 Dev Drive (a volume for developers) for your work, unpacking onto the Dev Drive makes even the first start fast. On a Dev Drive, Defender runs in "performance mode" and scans files after they are opened (Defender protection stays on). In our check (same machine), the window appeared in about 3 seconds. See Microsoft's description for how to set up a Dev Drive.

3. Run

In File Explorer, open the bin folder of the unpacked folder and double-click blinkgtk_browser.exe. Without an argument it opens https://google.com/ (an internet connection is needed).

To open a page of your choice, use a Command Prompt (search for "cmd" in the Start menu), move to the bin folder of the unpacked folder, and run:

cd /d "C:\BlinkGTK\blinkgtk-1.2.6-build4-windows-x64\bin"
blinkgtk_browser.exe https://example.com/

The C:\BlinkGTK\... on the first line is an example. Replace it with the actual path where you unpacked it (you can copy the path from the File Explorer address bar). If you paste < and > as they are, the Command Prompt treats them as symbols and fails.

With a URL argument it opens that page.
blinkgtk_browser is a minimal sample that shows only what you need to embed BlinkGTK.

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Check that it works

• If a web page appears in the window, it works.

  

• The executable tells you the version you have. Trust this rather than the numbers on the site or in the documents.

> blinkgtk_browser.exe --version
BlinkGTK 1.2.6-build4 (Chromium 157.0.8103.38)

• If nothing appears, the window stays white, or it exits at once, see If something goes wrong.

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Requirements

OS	Windows 10 (64-bit) or later. We verified on Windows 11 Pro (builds 26200 and 26300); we have not verified on Windows 10
CPU	x64 (32-bit is not supported)
Disk space	About 1.4 GiB (ZIP 379 MiB + about 1,056 MiB unpacked; you need both while unpacking)
GTK4	Bundled. Do not install it separately (mixing it with a GTK4 installed another way may fail to link with the bundled one)
VC++ runtime	DLLs bundled (you do not need the redistributable installer)

The GitHub Releases page shows the same ZIP as "379 MB". Tools that count in units of 1,000,000 bytes show 397 MB.

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Embedding it in your app

The devel ZIP (blinkgtk-devel-1.2.6-build4-windows-x64.zip) contains the public API headers, the import libraries and the GTK4 development files.

• What you need to build: Visual Studio Build Tools (we checked 2026) with the "Desktop development with C++" workload, and the Windows SDK. If you do not have a build environment yet, section 0 of the bundled docs\building-with-blinkgtk-en.md explains how to install it, with screenshots. You do not need an environment to build Chromium.

  

  The Modify screen of Visual Studio Installer (Japanese UI). What you use to build apps is "Desktop development with C++" in the list on the left (ticked in this screenshot). "Desktop development with C++" under "Installation details" on the right is collapsed in this screenshot. Expand it and check that the Windows SDK is ticked. If you select something that was missing, let the installation run to the end. After installing, confirm that cl works by following "Check that it works" in section 0 of the bundled docs\building-with-blinkgtk-en.md. This screenshot was taken on a machine that already had it installed.

• Compiler options: /MD /DCOMPONENT_BUILD. On Japanese Windows with MSVC, add /utf-8 too (otherwise the Japanese comments in the headers cause warning C4819).

• The full procedure is in the bundled docs\building-with-blinkgtk-en.md (Japanese: docs\building-with-blinkgtk-ja.md). The devel ZIP contains the source of a minimal app and a batch file that builds it, in examples\.

• The GPU document and the environment-variable document are in Japanese only (there are no English versions yet).

Four things to note.

1. Do not write your own forward declarations of the public API (Windows only). The headers declare it with __declspec(dllimport); a declaration without it in the same translation unit makes clang warn. Use only the headers.
2. Free return values that the caller owns with g_free() (for example blink_handoff_meta_serialize()). This has been the rule since 1.2.3-build2.
3. To use the sandbox, link the static library lib\blinkgtk_sandbox.lib and call blink_gtk_sandbox_init() (Windows only; it cannot be called on Linux, so wrap it in #ifdef G_OS_WIN32 when you share code between the two).
4. When the main loop returns, call blink_gtk_shutdown() before exiting. With Windows versions up to 1.2.5-build1, leaving it out makes the process take more than 20 seconds to exit, and it ends abnormally (from 1.2.5-build2 it is done automatically, but calling it explicitly is still recommended). See "6. Shut down" at the end of the sample (blinkgtk_browser-windows.c) for where to call it.

The public API has 154 entry points. Of these 154, the only difference from Linux is one entry point: blink_web_view_attach_to_external_surface (Wayland only) is not on Windows (blink_gtk_sandbox_init() above is Windows-only and is not counted in that number).
We have called 66 of them and confirmed they work. How they are counted, and how to list the ones not yet called, is in §0 of the bundled docs\api-windows-notes-en.md.

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Upgrading from an earlier version

The steps are the same from any version.

1. Unpack the new ZIP into a separate folder and try it; if it is fine, replace the old folder.
2. If you embed BlinkGTK in your own app, rebuild it with the headers and libraries from the new devel ZIP (compatibility with the previous blinkgtk.dll was not checked).

Notes for each version:

From 1.2.5-build5 to 1.2.6-build4:

• Chromium is updated from 156.0.8078.79 to 157.0.8103.38. Users of earlier Windows releases should update with the common steps above. Compare how vertical text and typesetting look on your own pages.
• The public API is unchanged (154 public API functions; the call check covered 66 of them on 2026-11-06).
• A problem where a static page kept using CPU is fixed. A process that reads the whole screen back ran every 50 milliseconds even when the page had not changed. Over a 16-second window on a static page, the browser process's CPU time fell from about 6.5-7.1 seconds to about 0.5-0.7 seconds (2026-11-06, comparing 1.2.5-build5 with the same build with the fix switched off and on, two measurements each). When the page does change, it is redrawn as before (checked with a page whose color changes after it has been static).

From 1.2.5-build3 to 1.2.5-build5 (the Windows build did not publish build4 separately, so build4's content is included here):

• Chromium is updated from 156.0.8078.73 to 156.0.8078.79, incorporating 21 security fixes. Users of earlier Windows releases should update using the common steps above. The list of fixes is on the release page.
• File System Access now stops sensitive locations. If a location picked with showOpenFilePicker() or showDirectoryPicker() is inside C:\Windows, the C:\Program Files folders, %APPDATA%, %LOCALAPPDATA%, C:\ProgramData, .ssh, .gnupg, .config or the shell startup files in your home folder, the folder of the BlinkGTK executable or its profile, or is a UNC path that points to the local machine, it is not passed to the page and is rejected with AbortError. The home, Desktop, Documents and Downloads folders themselves are not passed either, but files and folders inside them can be picked. Checked: we opened the real picker and confirmed that protected locations are rejected and ordinary locations can be picked (Windows 11 Pro, 2026-11-02). Locations received by drag and drop have not been checked yet.

From 1.2.5-build2 to 1.2.5-build3:

• Chromium is updated from 156.0.8078.47 to 156.0.8078.73, incorporating security fixes. Users of earlier Windows releases should update using the common steps above.
• Theme following, automatic shutdown and the child-process executable from build2 are retained. For configuration, see the build1-to-build2 notes below.

From 1.2.5-build1 to 1.2.5-build2:

• Chromium stays at 156.0.8078.47. There are no changes to the typesetting and layout engine.
• The page color scheme now follows the light/dark setting of the GTK theme (default). This covers the page's prefers-color-scheme. Set the environment variable BLINKGTK_FOLLOW_GTK_THEME=0 to go back to always-light pages. Checked, with one page that switches colors by prefers-color-scheme: with GTK_THEME=Adwaita:dark the page is dark, with GTK_THEME=Adwaita it is light, and with 0 it stays light even under Adwaita:dark (Windows 11 Pro, one Intel Iris Xe machine, 2026-10-27). We did not check on Windows: the background of pages that do not specify color-scheme, standard parts such as scrollbars, or whether GTK follows the light/dark setting of the Windows system.
• The shutdown when the main loop returns is now done automatically. Up to 1.2.5-build1, leaving out blink_gtk_shutdown() made the process take more than 20 seconds to exit and end abnormally. Checked: the 1.2.5-build1 sample, which does not call it, run with the 1.2.5-build2 DLLs exits in about 1 second with exit code 0 when it opens about:blank and its window is closed (one Intel Iris Xe machine, one run). Calling it explicitly is still recommended (calling it twice is safe). To stop the automatic shutdown, set BLINKGTK_NO_AUTO_SHUTDOWN=1.
• The ZIP now contains bin\blinkgtk_subprocess.exe. It is the executable that BlinkGTK uses for child processes only when the main program does not link blinkgtk.dll directly. Normal apps that link blinkgtk.dll directly, such as blinkgtk_browser.exe, do not use it, and it is not meant to be run directly.
• The public API did not change (still 154 entry points).

From 1.2.4-build4 to 1.2.5-build1:

• Chromium moved from 155 to 156 (156.0.8078.47). Compare how vertical text and typesetting look on your own pages.
• Hanging punctuation and one-line warichu now work. blink_gtk_has_typesetting_feature() returns TRUE for both "hanging-punctuation:allow-end" and "warichu:single-line" (we checked that the answers match the actual behavior). If you wrote your own fallback on the assumption of FALSE, review it.
• The Linux 1.2.5 changes are included, and we checked them on Windows too (2026-10-26, once each, on the 1.2.5-build1 package):
  • The load-failed error number is passed as an integer (int). Checked: the argument is an integer, and -3 is passed when a load is replaced by another page.
  • is-loading returns to false when loading ends. Checked: true and false are notified around a load.
  • set_user_agent() also applies to a page opened with load_uri() and to reload(). Checked: navigator.userAgent is the specified value after both.
  • The zoom level (set_zoom_level()) is a factor (1.0 = 100%). Checked: after setting 2.0, get_zoom_level() returns 2.0 and window.devicePixelRatio doubles.
• Check your shutdown code (for existing apps): check that your app calls blink_gtk_shutdown() after the main loop (blink_gtk_run_main_loop()) returns. If it does not, with Windows versions up to 1.2.5-build1 the process takes more than 20 seconds to exit and ends abnormally. From 1.2.5-build2 it is done automatically, but calling it explicitly is still recommended.
• The public API did not change (still 154 entry points).

From 1.2.4-build2 to 1.2.4-build4:

• The public API did not change (still 154 entry points; the header declarations are the same, only the comments changed).
• If you decide based on blink_gtk_has_typesetting_feature(): the Windows 1.2.4-build2 returned TRUE for "hanging-punctuation:allow-end", which was wrong; the Windows engine does not include hanging punctuation and it does not work. This version returns FALSE for both names (allow-end and warichu:single-line). Do not decide with CSS.supports or computed values (they return true even where the typesetting is not included).
• The screenshot API (blink_web_view_capture_screenshot_async() and similar): in Linux 1.2.4-build3, a screenshot on the software path changed to return the content at the time of the request. This change is included, but we have not checked it on Windows.
• GPU path: it is off by default, so you need to do nothing (see The experimental GPU path).
• The bundled GTK changed: gtk-4-1.dll is now a Vulkan-enabled build (about 1 MB larger). The default path, without the environment variable, does not change.

From 1.2.3 or earlier: use the steps above as they are. The first Windows 1.2.4 is 1.2.4-build2 (Chromium moved from 154 to 155). Up to 1.2.3-build4, a process could crash when an internal assumption failed. From 1.2.4 that check is disabled in the build.

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Differences from the Linux version

	Linux	Windows
Install	RPM / DEB / tarball	ZIP (MSI later)
GTK4	OS package	Bundled
How rendered output is handed to GTK	software / EGL	software by default. There is no EGL on Windows. An experimental GPU path can be selected with an environment variable (below)
blink_web_view_attach_to_external_surface	Yes	No (Wayland only)
Hanging punctuation typesetting	Yes (from 1.2.4-build1)	Yes (from 1.2.5-build1)
Warichu (inline cutting notes) typesetting (one-line cases)	Yes (from 1.2.4-build3)	Yes (from 1.2.5-build1)
Japanese vertical text layout	Experimental adjustment off by default	Same (off by default)

The experimental vertical-text adjustment (it aligns vertical lines inside multi-column layouts to the column grid) is off by default on both Linux and Windows.
To turn it on, add --enable-blink-features=CJKVerticalColumnFragmentation to the executable's command line (passing arguments to blink_gtk_init() from your app does not reach it).
We have not compared the rendered output of the two operating systems side by side, so there is no guarantee that the layout matches.

The environment variable BLINKGTK_GPU_MODE does not change how rendering is handed over on Windows. Even with egl, the hand-over to GTK is the same as software (Chromium's internal rendering may differ; we have not measured the result). To try the GPU, use BLINKGTK_WIN_GPU_PATH below.
When you set an environment variable in cmd, put it in quotes like set "NAME=value" (with set NAME=value && … a trailing space becomes part of the value).

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The experimental GPU path

Only when you set the environment variable BLINKGTK_WIN_GPU_PATH=vulkan, the result of Chromium's GPU compositing is handed to GTK's Vulkan renderer without being copied back into CPU memory (the usual path first copies the screen drawn by the GPU into CPU memory). A Vulkan-capable GPU and driver are required.

set "BLINKGTK_WIN_GPU_PATH=vulkan" && blinkgtk_browser.exe

• It is experimental and confirmed on one Intel Iris Xe machine only. Other GPUs and drivers are unconfirmed. It is off by default.
• At the same frames per second, CPU use was 12–26% lower on a moving page and about 50% lower on a still page (relative to the usual path), and the GPU was used 5–14%. Each is a single 120-second measurement, taken when this path was introduced. We have not measured power (watts).
• Not checked: changes of the screen scaling (DPI), and multiple windows. Even on a still page it copies about 60 times a second (the GPU is used about 14%).
• When Vulkan is not available (with a standard GTK, and with a simulated condition that points the Vulkan driver to a file that does not exist), it did not crash and the display did not break. We have not checked a machine that really has no driver.
• Usage, what we checked and the limits are in §1 of the bundled docs\gpu-modes-ja.md (Japanese only).

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If something goes wrong

• If the window stays white or it exits at once: (1) start blinkgtk_browser.exe --enable-logging and note the messages printed in the console; (2) check that the ZIP is not corrupted with SHA256SUMS; (3) check that you have not mixed in a GTK4 installed another way. If that does not fix it, report it (below) with the messages you noted.
• Bundled documents: §1 to §3 of docs\troubleshooting-en.md (Japanese: docs\troubleshooting-ja.md) have things to try, a symptom index and how to report (§4 and later are for people who build Chromium itself). For symptoms that are not there, please report them.
• Documentation entry point: docs\00-index-en.md (Japanese: docs\00-index-ja.md). Installation is docs\INSTALLATION-en.md, Windows-specific notes on the API are docs\api-windows-notes-en.md, and environment variables are in docs\environment-variables-ja.md (Japanese only).
• Reports and questions: please use Issues of blinkgtk-dist. Include the version (the output of --version), the Windows build number and the steps to reproduce.

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Change history

Date	Change
2026-10-11	1.2.4-build2 (Chromium 155)
2026-10-18	Updated for 1.2.4-build4: bundled Vulkan-enabled GTK, the experimental GPU path, and the corrected answers of blink_gtk_has_typesetting_feature
2026-10-19	Reorganized the page: separate sections for running it, checking that it works, and upgrading from an earlier version
2026-10-19	Added a "what you need depends on what you want to do" table and a pointer to installing the build environment
2026-10-21	Added screenshots of the unpacked folder, the browser window and Visual Studio Installer
2026-10-21	Fixed the run steps (double-click, Command Prompt), the download link, the Visual Studio screenshot note, added the WebKitGTK name correspondence, and reworked the upgrade steps
2026-10-21	Added the difference in load-changed values, how to replace the path in the command, and what to check in the Visual Studio screenshot
2026-10-23	Updated for 1.2.5-build1: Chromium 156, hanging punctuation and one-line warichu included, upgrade notes from 1.2.4-build4 added
2026-10-24	Added a note that the first start right after unpacking can be slow
2026-10-25	Added a note that unpacking onto a Dev Drive makes the first start fast
2026-10-26	Added the results of checking load-failed, is-loading, set_user_agent and zoom_level on Windows 1.2.5-build1, and a note on shutdown (blink_gtk_shutdown())
2026-10-27	The automatic shutdown is now stated as available from 1.2.5-build2
2026-10-27	Updated for 1.2.5-build2: version numbers and file names; added the "From 1.2.5-build1 to 1.2.5-build2" notes (theme following, automatic shutdown, the child-process executable)
2026-10-30	Updated for 1.2.5-build3: Chromium 156.0.8078.73 security update, upgrade steps, and license-file information
2026-11-02	Updated for 1.2.5-build5: Chromium 156.0.8078.79 security update, File System Access protection, and upgrade steps from build3
2026-11-07	Updated for 1.2.6-build4: Chromium 157.0.8103.38, the fix for CPU use on a static page, and upgrade steps from build5