diff --git a/README.md b/README.md
index ad47cd6..203baa2 100644
--- a/README.md
+++ b/README.md
@@ -68,7 +68,7 @@ You can find more examples on how to use rxjs-probe in [rxjs-probe-examples GitH
 ## 🔎 Probe Performers
 
 - [Probe Performer](https://github.com/a179346/rxjs-probe-examples/tree/main?tab=readme-ov-file#-custom-probe-performer) - The customizable health check performer
-- [Http Probe Performer](https://github.com/a179346/rxjs-probe/tree/main/packages/http-probe-performer#readme) - send HTTP GET requests to perform the health check.
+- [Http Probe Performer](https://github.com/a179346/rxjs-probe/tree/main/packages/http-probe-performer#readme) - Sending HTTP GET requests to perform the health check.
 
 ## 🤝 Contributing
 
diff --git a/packages/core/README.md b/packages/core/README.md
index ad47cd6..203baa2 100644
--- a/packages/core/README.md
+++ b/packages/core/README.md
@@ -68,7 +68,7 @@ You can find more examples on how to use rxjs-probe in [rxjs-probe-examples GitH
 ## 🔎 Probe Performers
 
 - [Probe Performer](https://github.com/a179346/rxjs-probe-examples/tree/main?tab=readme-ov-file#-custom-probe-performer) - The customizable health check performer
-- [Http Probe Performer](https://github.com/a179346/rxjs-probe/tree/main/packages/http-probe-performer#readme) - send HTTP GET requests to perform the health check.
+- [Http Probe Performer](https://github.com/a179346/rxjs-probe/tree/main/packages/http-probe-performer#readme) - Sending HTTP GET requests to perform the health check.
 
 ## 🤝 Contributing
 
diff --git a/packages/core/src/index.ts b/packages/core/src/index.ts
index bd56117..5e97acc 100644
--- a/packages/core/src/index.ts
+++ b/packages/core/src/index.ts
@@ -15,7 +15,7 @@ import { forkJoin, Observable, race, repeat, switchMap, tap, timer } from 'rxjs'
  * Use this class to create a custom health check performer.
  *
  * Or leverage our predefined health check performers:
- * - [HttpProbePerformer](https://www.npmjs.com/package/@rxjs-probe/http-probe-performer)
+ * - [HttpProbePerformer](https://github.com/a179346/rxjs-probe/tree/main/packages/http-probe-performer)
  */
 export class ProbePerformer {
   /**
diff --git a/packages/http-probe-performer/__tests__/http-probe-performer.test.js b/packages/http-probe-performer/__tests__/http-probe-performer.test.js
index 29d1109..c0d83df 100644
--- a/packages/http-probe-performer/__tests__/http-probe-performer.test.js
+++ b/packages/http-probe-performer/__tests__/http-probe-performer.test.js
@@ -30,6 +30,18 @@ describe('HTTP Probe Performer', () => {
       expect(healthy).toEqual(true);
     }, 2000);
 
+    it('should return false when the status code is greater than 399', async () => {
+      const performer = new HttpProbePerformer({
+        host: 'localhost',
+        port: 3000,
+        path: '/not-found',
+      });
+
+      const observable = performer.createObservable(2);
+      const healthy = await firstValueFrom(observable);
+      expect(healthy).toEqual(false);
+    }, 2000);
+
     it('should return false when timeoutd', async () => {
       const performer = new HttpProbePerformer({
         host: 'localhost',
diff --git a/packages/http-probe-performer/__tests__/test-server.test.js b/packages/http-probe-performer/__tests__/test-server.test.js
index 552fd76..2adf148 100644
--- a/packages/http-probe-performer/__tests__/test-server.test.js
+++ b/packages/http-probe-performer/__tests__/test-server.test.js
@@ -14,6 +14,10 @@ module.exports = {
         }, responseTimeout);
       });
 
+      app.get('/not-found', (req, res) => {
+        res.status(404).send();
+      });
+
       server = app.listen(3000, () => {
         resolve();
       });
diff --git a/packages/http-probe-performer/src/index.ts b/packages/http-probe-performer/src/index.ts
index 77165bf..097b1b4 100644
--- a/packages/http-probe-performer/src/index.ts
+++ b/packages/http-probe-performer/src/index.ts
@@ -55,7 +55,7 @@ export class HttpProbePerformer extends ProbePerformer {
         credentials: 'same-origin',
       });
 
-      if (response.status < 200 || response.status >= 300) {
+      if (response.status < 200 || response.status >= 400) {
         throw new Error(`HTTP status code: ${response.status}`);
       }
     });