diff --git a/packages/core/package.json b/packages/core/package.json
index f898caa41e31..f54a5e984958 100644
--- a/packages/core/package.json
+++ b/packages/core/package.json
@@ -54,6 +54,7 @@
     "lint:fix": "OXLINT_TSGOLINT_DANGEROUSLY_SUPPRESS_PROGRAM_DIAGNOSTICS=true oxlint . --fix --type-aware",
     "lint": "OXLINT_TSGOLINT_DANGEROUSLY_SUPPRESS_PROGRAM_DIAGNOSTICS=true oxlint . --type-aware",
     "lint:es-compatibility": "es-check es2020 ./build/cjs/*.js && es-check es2020 ./build/esm/*.js --module",
+    "bench": "vitest bench",
     "test": "vitest run",
     "test:watch": "vitest --watch",
     "yalc:publish": "yalc publish --push --sig"
diff --git a/packages/core/test/bench/capture-exception.bench.ts b/packages/core/test/bench/capture-exception.bench.ts
new file mode 100644
index 000000000000..a4f8dab1697f
--- /dev/null
+++ b/packages/core/test/bench/capture-exception.bench.ts
@@ -0,0 +1,53 @@
+import { bench, describe } from 'vitest';
+import {
+  addBreadcrumb,
+  captureException,
+  getCurrentScope,
+  getIsolationScope,
+  setCurrentClient,
+} from '../../src';
+import { getDefaultTestClientOptions, TestClient } from '../mocks/client';
+import { clearGlobalScope } from '../testutils';
+
+function setupClient() {
+  clearGlobalScope();
+  getCurrentScope().clear();
+  getIsolationScope().clear();
+
+  const client = new TestClient(
+    getDefaultTestClientOptions({
+      dsn: 'https://username@domain/123',
+      enableSend: true,
+      release: '1.0.0',
+      environment: 'production',
+    }),
+  );
+  setCurrentClient(client);
+  client.init();
+  return client;
+}
+
+describe('captureException - minimal scope', () => {
+  setupClient();
+
+  bench('captureException(new Error(...))', () => {
+    captureException(new Error('Something went wrong'));
+  });
+});
+
+describe('captureException - realistic scope', () => {
+  setupClient();
+
+  getCurrentScope().setUser({ id: '123', email: 'user@example.com' });
+  getCurrentScope().setTag('service', 'api-gateway');
+  getCurrentScope().setTag('region', 'us-east-1');
+  getCurrentScope().setTag('version', '2.1.0');
+  getCurrentScope().setExtra('request_id', 'req-abc-123');
+  for (let i = 0; i < 10; i++) {
+    addBreadcrumb({ message: `Action ${i}`, category: 'http', level: 'info' });
+  }
+
+  bench('captureException(new Error(...))', () => {
+    captureException(new Error('Something went wrong'));
+  });
+});
diff --git a/packages/core/test/bench/startSpan.bench.ts b/packages/core/test/bench/startSpan.bench.ts
new file mode 100644
index 000000000000..b090d13c994a
--- /dev/null
+++ b/packages/core/test/bench/startSpan.bench.ts
@@ -0,0 +1,105 @@
+import { bench, describe } from 'vitest';
+import {
+  addBreadcrumb,
+  getCurrentScope,
+  getIsolationScope,
+  setCurrentClient,
+  startSpan,
+} from '../../src';
+import { getDefaultTestClientOptions, TestClient } from '../mocks/client';
+import { clearGlobalScope } from '../testutils';
+
+function setupClient() {
+  clearGlobalScope();
+  getCurrentScope().clear();
+  getIsolationScope().clear();
+
+  const client = new TestClient(
+    getDefaultTestClientOptions({
+      dsn: 'https://username@domain/123',
+      enableSend: true,
+      tracesSampleRate: 1,
+      release: '1.0.0',
+      environment: 'production',
+    }),
+  );
+  setCurrentClient(client);
+  client.init();
+  return client;
+}
+
+function addRealisticScopeData() {
+  getCurrentScope().setUser({ id: '123', email: 'user@example.com' });
+  getCurrentScope().setTag('service', 'api-gateway');
+  getCurrentScope().setTag('region', 'us-east-1');
+  getCurrentScope().setTag('version', '2.1.0');
+  getCurrentScope().setExtra('request_id', 'req-abc-123');
+  for (let i = 0; i < 10; i++) {
+    addBreadcrumb({ message: `Action ${i}`, category: 'http', level: 'info' });
+  }
+}
+
+describe('startSpan pipeline - realistic scope', () => {
+  setupClient();
+  addRealisticScopeData();
+
+  bench('single root span', () => {
+    startSpan({ name: 'GET /api/users', op: 'http.server' }, () => {
+      // span lifecycle only
+    });
+  });
+
+  bench('root span + 5 child spans', () => {
+    startSpan({ name: 'GET /api/users', op: 'http.server' }, () => {
+      for (let i = 0; i < 5; i++) {
+        startSpan({ name: `SELECT * FROM users WHERE id = $${i + 1}`, op: 'db' }, span => {
+          span.setAttribute('db.system', 'postgresql');
+          span.setAttribute('db.name', 'mydb');
+        });
+      }
+    });
+  });
+
+  bench('root span + 10 child spans', () => {
+    startSpan({ name: 'GET /api/users', op: 'http.server' }, () => {
+      for (let i = 0; i < 10; i++) {
+        startSpan(
+          { name: i < 5 ? `db.query.${i}` : `http.request.${i}`, op: i < 5 ? 'db' : 'http.client' },
+          span => {
+            span.setAttribute('key', 'value');
+          },
+        );
+      }
+    });
+  });
+
+  bench('root span + 100 child spans', () => {
+    startSpan({ name: 'GET /api/users', op: 'http.server' }, () => {
+      for (let i = 0; i < 100; i++) {
+        startSpan({ name: `operation.${i}`, op: 'db' }, span => {
+          span.setAttribute('db.system', 'postgresql');
+        });
+      }
+    });
+  });
+
+  bench('root span + 1000 child spans', () => {
+    startSpan({ name: 'GET /api/users', op: 'http.server' }, () => {
+      for (let i = 0; i < 1000; i++) {
+        startSpan({ name: `operation.${i}`, op: 'db' }, span => {
+          span.setAttribute('db.system', 'postgresql');
+        });
+      }
+    });
+  });
+
+  bench('root span + 10000 child spans', () => {
+    startSpan({ name: 'GET /api/users', op: 'http.server' }, () => {
+      for (let i = 0; i < 10000; i++) {
+        startSpan({ name: `operation.${i}`, op: 'db' }, span => {
+          span.setAttribute('db.system', 'postgresql');
+        });
+      }
+    });
+  });
+});