diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6158708..a1d4a5f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,10 +6,12 @@ The format is based on [Keep a Changelog].
 ## Unreleased
 ### Formatters
 * `biome` ([#339]).
+* `gdformat` for [gdscript](https://docs.godotengine.org/en/stable/tutorials/scripting/gdscript/gdscript_basics.html) ([#342]).
 * `prettier-json-stringify` ([#183]).
 
-[#339]: https://github.com/radian-software/apheleia/pull/339
 [#183]: https://github.com/radian-software/apheleia/pull/183
+[#339]: https://github.com/radian-software/apheleia/pull/339
+[#342]: https://github.com/radian-software/apheleia/pull/342
 
 ## 4.3 (released 2024-11-12)
 ### Features
diff --git a/apheleia-formatters.el b/apheleia-formatters.el
index 092b41e..7366262 100644
--- a/apheleia-formatters.el
+++ b/apheleia-formatters.el
@@ -64,6 +64,7 @@
     (fish-indent . ("fish_indent"))
     (fourmolu . ("fourmolu"))
     (gawk . ("gawk" "-f" "-" "--pretty-print=-"))
+    (gdformat . ("gdformat" "-"))
     (gleam . ("gleam" "format" "--stdin"))
     (gofmt . ("gofmt"))
     (gofumpt . ("gofumpt"))
@@ -328,6 +329,8 @@ rather than using this system."
     (elm-mode . elm-format)
     (emacs-lisp-mode . lisp-indent)
     (fish-mode . fish-indent)
+    (gdscript-mode . gdformat)
+    (gdscript-ts-mode . gdformat)
     (gleam-ts-mode . gleam)
     (go-mode . gofmt)
     (go-ts-mode . gofmt)
diff --git a/test/formatters/installers/gdformat.bash b/test/formatters/installers/gdformat.bash
new file mode 100644
index 0000000..4ecfae1
--- /dev/null
+++ b/test/formatters/installers/gdformat.bash
@@ -0,0 +1,2 @@
+apt-get install -y python3-pip
+pip3 install "gdtoolkit==4.*"
diff --git a/test/formatters/samplecode/gdformat/in.gd b/test/formatters/samplecode/gdformat/in.gd
new file mode 100644
index 0000000..9e30e3d
--- /dev/null
+++ b/test/formatters/samplecode/gdformat/in.gd
@@ -0,0 +1,9 @@
+class X:
+	var x=[1,2,{'a':1}]
+	var y=[1,2,3,]     # trailing comma
+	func foo(a:int,b,c=[1,2,3]):
+		if a in c and \
+		   b > 100:
+			print('foo')
+func bar():
+	print('bar')
diff --git a/test/formatters/samplecode/gdformat/out.gd b/test/formatters/samplecode/gdformat/out.gd
new file mode 100644
index 0000000..bede6f6
--- /dev/null
+++ b/test/formatters/samplecode/gdformat/out.gd
@@ -0,0 +1,15 @@
+class X:
+	var x = [1, 2, {"a": 1}]
+	var y = [
+		1,
+		2,
+		3,
+	]  # trailing comma
+
+	func foo(a: int, b, c = [1, 2, 3]):
+		if a in c and b > 100:
+			print("foo")
+
+
+func bar():
+	print("bar")