diff --git a/testing/web-platform/tests/requestidlecallback/deadline-max-rAF-dynamic.html b/testing/web-platform/tests/requestidlecallback/deadline-max-rAF-dynamic.html
new file mode 100644
index 0000000000000..43eebd7641be0
--- /dev/null
+++ b/testing/web-platform/tests/requestidlecallback/deadline-max-rAF-dynamic.html
@@ -0,0 +1,31 @@
+<!DOCTYPE html>
+<title>window.requestIdleCallback max idle period deadline (requestAnimationFrame).</title>
+<meta name="timeout" content="long">
+<link rel="author" title="Noam Rosenthal" href="mailto:noam@webkit.org" />
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="resources/ric-utils.js"></script>
+<script>
+
+promise_test(async () => {
+  for (let i = 0; i < getRICRetryCount(); ++i) {
+    const {before, after} = await new Promise(resolve => requestIdleCallback(async deadline => {
+      const before = deadline.timeRemaining();
+      const animationFramePromise = new Promise(requestAnimationFrame);
+      const after = deadline.timeRemaining();
+
+      // Waiting till rAF is handled before the next iteration, to avoid residual callacks between iterations.
+      await animationFramePromise;
+      resolve({before, after})
+    }))
+
+    assert_less_than_equal(after, before)
+    assert_less_than_equal(after, getPendingRenderDeadlineCap())
+  }
+
+}, 'Check that the deadline is changed if there is a new requestAnimationFrame from within requestIdleCallback.');
+</script>
+<h1>Test of requestIdleCallback deadline behavior</h1>
+<p>The test can pass accidentally as idle deadlines have a maximum but they can always be shorter.
+It runs multiple times to expose potential failures.</p>
+<div id="log"></div>
diff --git a/testing/web-platform/tests/requestidlecallback/deadline-max-rAF.html b/testing/web-platform/tests/requestidlecallback/deadline-max-rAF.html
new file mode 100644
index 0000000000000..314f250254f95
--- /dev/null
+++ b/testing/web-platform/tests/requestidlecallback/deadline-max-rAF.html
@@ -0,0 +1,21 @@
+<!DOCTYPE html>
+<title>window.requestIdleCallback max idle period deadline (requestAnimationFrame).</title>
+<meta name="timeout" content="long">
+<link rel="author" title="Noam Rosenthal" href="mailto:noam@webkit.org" />
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="resources/ric-utils.js"></script>
+<script>
+
+promise_test(async done => {
+  for (let i = 0; i < getRICRetryCount(); ++i) {
+    requestAnimationFrame(() => {})
+    assert_less_than_equal(await getDeadlineForNextIdleCallback(), getPendingRenderDeadlineCap())
+  }
+
+}, 'Check that the deadline is less than 16ms when there is a pending animation frame.');
+</script>
+<h1>Test of requestIdleCallback deadline behavior</h1>
+<p>The test can pass accidentally as idle deadlines have a maximum but they can always be shorter.
+It runs multiple times to expose potential failures.</p>
+<div id="log"></div>
diff --git a/testing/web-platform/tests/requestidlecallback/deadline-max-timeout-dynamic.html b/testing/web-platform/tests/requestidlecallback/deadline-max-timeout-dynamic.html
new file mode 100644
index 0000000000000..169e6db548530
--- /dev/null
+++ b/testing/web-platform/tests/requestidlecallback/deadline-max-timeout-dynamic.html
@@ -0,0 +1,31 @@
+<!DOCTYPE html>
+<title>window.requestIdleCallback max idle period deadline (dynamic timoeout).</title>
+<meta name="timeout" content="long">
+<link rel="author" title="Noam Rosenthal" href="mailto:noam@webkit.org" />
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="resources/ric-utils.js"></script>
+<script>
+
+promise_test(async () => {
+  for (let i = 0; i < getRICRetryCount(); ++i) {
+    for (const timeout of [10, 20, 30]) {
+      const {before, after} = await new Promise(resolve => requestIdleCallback(async deadline => {
+        const before = deadline.timeRemaining();
+        const timerPromise = new Promise(resolve => step_timeout(resolve, timeout));
+        const after = deadline.timeRemaining();
+        await timerPromise;
+        resolve({before, after})
+      }))
+
+      assert_less_than_equal(after, before)
+      assert_less_than_equal(after, timeout)
+    }
+  }
+
+}, 'Check that the deadline is changed if there is a new timeout from within requestIdleCallback.');
+</script>
+<h1>Test of requestIdleCallback deadline behavior</h1>
+<p>The test can pass accidentally as idle deadlines have a maximum but they can always be shorter.
+It runs multiple times to expose potential failures.</p>
+<div id="log"></div>
diff --git a/testing/web-platform/tests/requestidlecallback/deadline-max.html b/testing/web-platform/tests/requestidlecallback/deadline-max.html
new file mode 100644
index 0000000000000..e33341ac9dd97
--- /dev/null
+++ b/testing/web-platform/tests/requestidlecallback/deadline-max.html
@@ -0,0 +1,20 @@
+<!DOCTYPE html>
+<title>window.requestIdleCallback max idle period deadline.</title>
+<meta name="timeout" content="long">
+<link rel="author" title="Noam Rosenthal" href="mailto:noam@webkit.org" />
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="resources/ric-utils.js"></script>
+<script>
+
+promise_test(async done => {
+  for (let i = 0; i < getRICRetryCount(); ++i)
+    assert_less_than_equal(await getDeadlineForNextIdleCallback(), 50)
+
+}, 'Check that the deadline is less than 50ms.');
+</script>
+<h1>Test of requestIdleCallback deadline behavior</h1>
+<p>This test validates that deadlines returned for requestIdleCallback are less than 50ms.</p>
+<p>The test can pass accidentally as idle deadlines have a maximum but they can always be shorter.
+It runs multiple times to expose potential failures.</p>
+<div id="log"></div>
diff --git a/testing/web-platform/tests/requestidlecallback/resources/ric-utils.js b/testing/web-platform/tests/requestidlecallback/resources/ric-utils.js
new file mode 100644
index 0000000000000..d6d22767a98ee
--- /dev/null
+++ b/testing/web-platform/tests/requestidlecallback/resources/ric-utils.js
@@ -0,0 +1,14 @@
+function getDeadlineForNextIdleCallback() {
+    return new Promise(
+        resolve =>
+            requestIdleCallback(deadline => resolve(deadline.timeRemaining()))
+    );
+}
+
+function getPendingRenderDeadlineCap() {
+    return 1000 / 60;
+}
+
+function getRICRetryCount() {
+    return 10;
+}
\ No newline at end of file
