diff --git a/packages/core/src/utils/fromString.ts b/packages/core/src/utils/fromString.ts
new file mode 100644
index 00000000..5371abcc
--- /dev/null
+++ b/packages/core/src/utils/fromString.ts
@@ -0,0 +1,15 @@
+export default function fromString(value: any) {
+  if (value.match(/^\d*(\.\d+)?$/)) {
+    return Number(value)
+  }
+
+  if (value === 'true') {
+    return true
+  }
+
+  if (value === 'false') {
+    return false
+  }
+
+  return value
+}
diff --git a/packages/core/src/utils/injectExtensionAttributesToParseRule.ts b/packages/core/src/utils/injectExtensionAttributesToParseRule.ts
index 0cd42dd6..185d7098 100644
--- a/packages/core/src/utils/injectExtensionAttributesToParseRule.ts
+++ b/packages/core/src/utils/injectExtensionAttributesToParseRule.ts
@@ -1,5 +1,6 @@
 import { ParseRule } from 'prosemirror-model'
 import { ExtensionAttribute } from '../types'
+import fromString from './fromString'
 
 /**
  * This function merges extension attributes into parserule attributes (`attrs` or `getAttrs`).
@@ -29,7 +30,7 @@ export default function injectExtensionAttributesToParseRule(parseRule: ParseRul
           const attributes = item.attribute.parseHTML
             ? item.attribute.parseHTML(node as HTMLElement) || {}
             : {
-              [item.name]: (node as HTMLElement).getAttribute(item.name),
+              [item.name]: fromString((node as HTMLElement).getAttribute(item.name)),
             }
 
           const filteredAttributes = Object.fromEntries(Object.entries(attributes)