diff --git a/src/js/finder.js b/src/js/finder.js
index 172fbc5..5e6500a 100644
--- a/src/js/finder.js
+++ b/src/js/finder.js
@@ -9,7 +9,8 @@ import {
 } from './parser.js';
 import {
   isContentEditable, isCustomElement, isFocusVisible, isFocusable,
-  isInShadowTree, isVisible, resolveContent, sortNodes, traverseNode
+  isFocusableArea, isInShadowTree, isVisible, resolveContent, sortNodes,
+  traverseNode
 } from './utility.js';
 
 /* constants */
@@ -1064,16 +1065,14 @@ export class Finder {
           break;
         }
         case 'focus': {
-          if (node === this.#document.activeElement &&
-              (node.hasAttribute('autofocus') || node.tabIndex >= 0) &&
+          if (node === this.#document.activeElement && isFocusableArea(node) &&
               isFocusable(node)) {
             matched.add(node);
           }
           break;
         }
         case 'focus-visible': {
-          if (node === this.#document.activeElement &&
-              (node.hasAttribute('autofocus') || node.tabIndex >= 0)) {
+          if (node === this.#document.activeElement && isFocusableArea(node)) {
             let bool;
             if (isFocusVisible(node)) {
               bool = true;
@@ -1096,7 +1095,7 @@ export class Finder {
         case 'focus-within': {
           let bool;
           let current = this.#document.activeElement;
-          if (current.hasAttribute('autofocus') || current.tabIndex >= 0) {
+          if (isFocusableArea(current)) {
             while (current) {
               if (current === node) {
                 bool = true;
diff --git a/src/js/utility.js b/src/js/utility.js
index 69f95e7..a983151 100644
--- a/src/js/utility.js
+++ b/src/js/utility.js
@@ -416,6 +416,98 @@ export const isFocusVisible = node => {
   return !!res;
 };
 
+/**
+ * is focusable area
+ * @param {object} node - Element node
+ * @returns {boolean} - result
+ */
+export const isFocusableArea = node => {
+  if (node?.nodeType === ELEMENT_NODE) {
+    if (!node.isConnected) {
+      return false;
+    }
+    const window = node.ownerDocument.defaultView;
+    if (node instanceof window.HTMLElement) {
+      if (!Number.isNaN(parseInt(node.getAttribute('tabindex')))) {
+        return true;
+      }
+      if (isContentEditable(node)) {
+        return true;
+      }
+      const { localName, parentNode } = node;
+      switch (localName) {
+        case 'a': {
+          if (node.href || node.hasAttribute('href')) {
+            return true;
+          }
+          return false;
+        }
+        case 'iframe': {
+          return true;
+        }
+        case 'input': {
+          if (node.disabled || node.hasAttribute('disabled') ||
+              node.hidden || node.hasAttribute('hidden')) {
+            return false;
+          }
+          return true;
+        }
+        case 'summary': {
+          if (parentNode.localName === 'details') {
+            let child = parentNode.firstElementChild;
+            while (child) {
+              if (child.localName === 'summary') {
+                return node === child;
+              }
+              child = child.nextElementSibling;
+            }
+          }
+          return false;
+        }
+        default: {
+          const keys = new Set(['button', 'select', 'textarea']);
+          if (keys.has(localName) &&
+              !(node.disabled || node.hasAttribute('disabled'))) {
+            return true;
+          }
+          return false;
+        }
+      }
+    } else if (node instanceof window.SVGElement) {
+      if (!Number.isNaN(parseInt(node.getAttributeNS(null, 'tabindex')))) {
+        const keys = new Set([
+          'clipPath', 'defs', 'desc', 'linearGradient', 'marker', 'mask',
+          'metadata', 'pattern', 'radialGradient', 'script', 'style', 'symbol',
+          'title'
+        ]);
+        const ns = 'http://www.w3.org/2000/svg';
+        let bool;
+        let refNode = node;
+        while (refNode.namespaceURI === ns) {
+          bool = keys.has(refNode.localName);
+          if (bool) {
+            break;
+          }
+          if (refNode?.parentNode?.namespaceURI === ns) {
+            refNode = refNode.parentNode;
+          } else {
+            break;
+          }
+        }
+        if (bool) {
+          return false;
+        }
+        return true;
+      }
+      if (node.localName === 'a' &&
+          (node.href || node.hasAttributeNS(null, 'href'))) {
+        return true;
+      }
+    }
+  }
+  return false;
+};
+
 /**
  * is focusable
  * NOTE: workaround for jsdom issue: https://github.com/jsdom/jsdom/issues/3464
diff --git a/test/utility.test.js b/test/utility.test.js
index a304617..4151580 100644
--- a/test/utility.test.js
+++ b/test/utility.test.js
@@ -1154,6 +1154,221 @@ describe('utility functions', () => {
     });
   });
 
+  describe('is focasable area', () => {
+    const func = util.isFocusableArea;
+
+    it('should get false', () => {
+      const res = func();
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get false', () => {
+      const res = func(document);
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get false', () => {
+      const res = func(document.body);
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get false', () => {
+      const node = document.createElement('div');
+      const res = func(node);
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get false', () => {
+      const node = document.createElement('div');
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get true', () => {
+      const node = document.createElement('div');
+      node.tabIndex = -1;
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isTrue(res, 'result');
+    });
+
+    it('should get true', () => {
+      const node = document.createElement('div');
+      node.setAttribute('contenteditable', '');
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isTrue(res, 'result');
+    });
+
+    it('should get false', () => {
+      const node = document.createElement('a');
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get true', () => {
+      const node = document.createElement('a');
+      node.href = 'about:blank';
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isTrue(res, 'result');
+    });
+
+    it('should get true', () => {
+      const node = document.createElement('iframe');
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isTrue(res, 'result');
+    });
+
+    it('should get true', () => {
+      const node = document.createElement('input');
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isTrue(res, 'result');
+    });
+
+    it('should get false', () => {
+      const node = document.createElement('input');
+      node.disabled = true;
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get false', () => {
+      const node = document.createElement('input');
+      node.setAttribute('disabled', '');
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get false', () => {
+      const node = document.createElement('input');
+      node.hidden = true;
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get false', () => {
+      const node = document.createElement('input');
+      node.setAttribute('hidden', '');
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get false', () => {
+      const node = document.createElement('summary');
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get true', () => {
+      const parent = document.createElement('details');
+      const node = document.createElement('summary');
+      parent.appendChild(node);
+      document.body.appendChild(parent);
+      const res = func(node);
+      assert.isTrue(res, 'result');
+    });
+
+    it('should get false', () => {
+      const parent = document.createElement('details');
+      const nodeBefore = document.createElement('summary');
+      const node = document.createElement('summary');
+      parent.appendChild(nodeBefore);
+      parent.appendChild(node);
+      document.body.appendChild(parent);
+      const res = func(node);
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get true', () => {
+      const parent = document.createElement('details');
+      const nodeBefore = document.createElement('div');
+      const node = document.createElement('summary');
+      parent.appendChild(nodeBefore);
+      parent.appendChild(node);
+      document.body.appendChild(parent);
+      const res = func(node);
+      assert.isTrue(res, 'result');
+    });
+
+    it('should get true', () => {
+      const node = document.createElement('button');
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isTrue(res, 'result');
+    });
+
+    it('should get false', () => {
+      const node = document.createElement('button');
+      node.disabled = true;
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get false', () => {
+      const node =
+        document.createElementNS('http://www.w3.org/2000/svg', 'svg');
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get true', () => {
+      const node =
+        document.createElementNS('http://www.w3.org/2000/svg', 'svg');
+      node.tabIndex = -1;
+      document.body.appendChild(node);
+      const res = func(node);
+      assert.isTrue(res, 'result');
+    });
+
+    it('should get true', () => {
+      const parent =
+        document.createElementNS('http://www.w3.org/2000/svg', 'svg');
+      const node =
+        document.createElementNS('http://www.w3.org/2000/svg', 'text');
+      node.tabIndex = -1;
+      parent.appendChild(node)
+      document.body.appendChild(parent);
+      const res = func(node);
+      assert.isTrue(res, 'result');
+    });
+
+    it('should get false', () => {
+      const parent =
+        document.createElementNS('http://www.w3.org/2000/svg', 'svg');
+      const node =
+        document.createElementNS('http://www.w3.org/2000/svg', 'mask');
+      node.tabIndex = -1;
+      parent.appendChild(node)
+      document.body.appendChild(parent);
+      const res = func(node);
+      assert.isFalse(res, 'result');
+    });
+
+    it('should get true', () => {
+      const parent =
+        document.createElementNS('http://www.w3.org/2000/svg', 'svg');
+      const node =
+        document.createElementNS('http://www.w3.org/2000/svg', 'a');
+      node.setAttribute('href', 'about:blank');
+      parent.appendChild(node)
+      document.body.appendChild(parent);
+      const res = func(node);
+      assert.isTrue(res, 'result');
+    });
+  });
+
   describe('is focusable', () => {
     const func = util.isFocusable;