diff --git a/webgpu/resources/js/rolling-average.js b/webgpu/resources/js/rolling-average.js
new file mode 100644
index 00000000..a2f36c97
--- /dev/null
+++ b/webgpu/resources/js/rolling-average.js
@@ -0,0 +1,20 @@
+// See https://webgpufundamentals.org/webgpu/lessons/webgpu-timing.html
+export default class RollingAverage {
+  #total = 0;
+  #samples = [];
+  #cursor = 0;
+  #numSamples;
+  constructor(numSamples = 30) {
+    this.#numSamples = numSamples;
+  }
+  addSample(v) {
+    if (!Number.isNaN(v) && Number.isFinite(v)) {
+      this.#total += v - (this.#samples[this.#cursor] || 0);
+      this.#samples[this.#cursor] = v;
+      this.#cursor = (this.#cursor + 1) % this.#numSamples;
+    }
+  }
+  get() {
+    return this.#total / this.#samples.length;
+  }
+}
diff --git a/webgpu/resources/js/timing-helper.js b/webgpu/resources/js/timing-helper.js
index 306fb32f..aa645924 100644
--- a/webgpu/resources/js/timing-helper.js
+++ b/webgpu/resources/js/timing-helper.js
@@ -4,6 +4,7 @@ function assert(cond, msg = '') {
   }
 }
 
+// See https://webgpufundamentals.org/webgpu/lessons/webgpu-timing.html
 export default class TimingHelper {
   #canTimestamp;
   #device;