diff --git a/.gitignore b/.gitignore
index 9b1c8b1..94c0d5f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,3 @@
 /dist
+/icon256.ico
+/icon512.png
diff --git a/Makefile b/Makefile
index 149aeed..2043a3b 100644
--- a/Makefile
+++ b/Makefile
@@ -15,8 +15,21 @@ macos:
 	./scripts/make-mac-bundle.sh dist/shark-macos
 
 clean:
-	rm -rf dist/*
+	rm -rf dist/* icon256.ico icon512.png
 
 # https://ebiten.org/documents/install.html#Debian_/_Ubuntu
 deps-debian:
 	sudo apt install libc6-dev libglu1-mesa-dev libgl1-mesa-dev libxcursor-dev libxi-dev libxinerama-dev libxrandr-dev libxxf86vm-dev libasound2-dev pkg-config
+
+icon256.ico: icon.png
+	magick convert icon.png -filter point -resize '800%' icon256.ico
+
+icon512.png: icon.png
+	magick convert icon.png -filter point -resize '1600%' PNG24:icon512.png
+
+shark.syso: icon256.ico
+	# needs `go install github.com/akavel/rsrc@latest`
+	~/go/bin/rsrc -ico icon256.ico -o shark.syso
+
+icon.icns: icon512.png
+	png2icns icon.icns icon512.png
diff --git a/icon.icns b/icon.icns
index 857c955..c589ae2 100644
Binary files a/icon.icns and b/icon.icns differ
diff --git a/shark.syso b/shark.syso
index f6f9806..fd9653b 100644
Binary files a/shark.syso and b/shark.syso differ