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+---
+name: Check if two objects are deeply equal
+---
+
+Check if two objects are deeply equal. This is used internally by `expect().toEqual()` in Bun's [test runner](/docs/test/writing).
+
+```ts#index.ts
+const a = { a: 1, b: 2, c: { d: 3 } };
+const b = { a: 1, b: 2, c: { d: 3 } };
+
+Bun.deepEquals(a, b); // true
+```
+
+---
+
+Pass `true` as a third argument to enable strict mode. This is used internally by `expect().toStrictEqual()` in Bun's [test runner](/docs/test/writing).
+
+The following examples would return `true` in non-strict mode but `false` in strict mode.
+
+```ts
+// undefined values
+Bun.deepEquals({}, { a: undefined }, true); // false
+
+// undefined in arrays
+Bun.deepEquals(["asdf"], ["asdf", undefined], true); // false
+
+// sparse arrays
+Bun.deepEquals([, 1], [undefined, 1], true); // false
+
+// object literals vs instances w/ same properties
+class Foo {
+  a = 1;
+}
+Bun.deepEquals(new Foo(), { a: 1 }, true); // false
+```
+
+---
+
+See [Docs > API > Utils](/docs/api/utils) for more useful utilities.