diff --git a/crates/bevy_window/src/window.rs b/crates/bevy_window/src/window.rs
index 1d08f68d77c11..d05679532806f 100644
--- a/crates/bevy_window/src/window.rs
+++ b/crates/bevy_window/src/window.rs
@@ -206,6 +206,14 @@ pub struct Window {
     ///
     /// This value has no effect on non-web platforms.
     pub canvas: Option<String>,
+    /// Whether or not to fit the canvas element's size to its parent element's size.
+    ///
+    /// **Warning**: this will not behave as expected for parents that set their size according to the size of their
+    /// children. This creates a "feedback loop" that will result in the canvas growing on each resize. When using this
+    /// feature, ensure the parent's size is not affected by its children.
+    ///
+    /// This value has no effect on non-web platforms.
+    pub fit_canvas_to_parent: bool,
     /// Whether or not to stop events from propagating out of the canvas element
     ///
     ///  When `true`, this will prevent common browser hotkeys like F5, F12, Ctrl+R, tab, etc.
@@ -274,6 +282,7 @@ impl Default for Window {
             transparent: false,
             focused: true,
             window_level: Default::default(),
+            fit_canvas_to_parent: false,
             prevent_default_event_handling: true,
             canvas: None,
             window_theme: None,
diff --git a/crates/bevy_winit/Cargo.toml b/crates/bevy_winit/Cargo.toml
index 5574b67438d71..c2d4efbedd2ea 100644
--- a/crates/bevy_winit/Cargo.toml
+++ b/crates/bevy_winit/Cargo.toml
@@ -45,7 +45,6 @@ winit = { version = "0.29", default-features = false, features = [
 [target.'cfg(target_arch = "wasm32")'.dependencies]
 wasm-bindgen = { version = "0.2" }
 web-sys = "0.3"
-
 crossbeam-channel = "0.5"
 
 [package.metadata.docs.rs]
diff --git a/crates/bevy_winit/src/system.rs b/crates/bevy_winit/src/system.rs
index 48ccc1e02f62e..44bcc43e6c76e 100644
--- a/crates/bevy_winit/src/system.rs
+++ b/crates/bevy_winit/src/system.rs
@@ -17,6 +17,9 @@ use winit::{
     event_loop::EventLoopWindowTarget,
 };
 
+#[cfg(target_arch = "wasm32")]
+use winit::platform::web::WindowExtWebSys;
+
 use crate::{
     converters::{
         self, convert_enabled_buttons, convert_window_level, convert_window_theme,
@@ -80,6 +83,17 @@ pub fn create_windows<F: QueryFilter + 'static>(
                 window: window.clone(),
             });
 
+        #[cfg(target_arch = "wasm32")]
+        {
+            if window.fit_canvas_to_parent {
+                let canvas = winit_window
+                    .canvas()
+                    .expect("window.canvas() can only be called in main thread.");
+                let style = canvas.style();
+                style.set_property("width", "100%").unwrap();
+                style.set_property("height", "100%").unwrap();
+            }
+        }
         window_created_events.send(WindowCreated { window: entity });
     }
 }
diff --git a/examples/wasm/index.html b/examples/wasm/index.html
index 0fa46de41877f..1688962669241 100644
--- a/examples/wasm/index.html
+++ b/examples/wasm/index.html
@@ -15,8 +15,6 @@
         background-size: 20px 20px;
       }
       canvas {
-        width: 100%;
-        height: 100%;
         background-color: white;
       }
     </style>
diff --git a/examples/window/window_settings.rs b/examples/window/window_settings.rs
index 31ea347e64db6..2e509e2fba7eb 100644
--- a/examples/window/window_settings.rs
+++ b/examples/window/window_settings.rs
@@ -17,6 +17,8 @@ fn main() {
                     name: Some("bevy.app".into()),
                     resolution: (500., 300.).into(),
                     present_mode: PresentMode::AutoVsync,
+                    // Tells wasm to resize the window according to the available canvas
+                    fit_canvas_to_parent: true,
                     // Tells wasm not to override default event handling, like F5, Ctrl+R etc.
                     prevent_default_event_handling: false,
                     window_theme: Some(WindowTheme::Dark),
diff --git a/tools/example-showcase/window-settings-wasm.patch b/tools/example-showcase/window-settings-wasm.patch
index 02e8965901869..5fcb1fba9556c 100644
--- a/tools/example-showcase/window-settings-wasm.patch
+++ b/tools/example-showcase/window-settings-wasm.patch
@@ -1,11 +1,13 @@
 diff --git a/crates/bevy_window/src/window.rs b/crates/bevy_window/src/window.rs
-index 7b5c75d38..8e9404b93 100644
+index 87cdfb050..1d87a0bf5 100644
 --- a/crates/bevy_window/src/window.rs
 +++ b/crates/bevy_window/src/window.rs
-@@ -245,8 +245,8 @@ impl Default for Window {
+@@ -266,9 +266,9 @@ impl Default for Window {
              transparent: false,
              focused: true,
              window_level: Default::default(),
+-            fit_canvas_to_parent: false,
++            fit_canvas_to_parent: true,
              prevent_default_event_handling: true,
 -            canvas: None,
 +            canvas: Some("#bevy".to_string()),