Login Page Test Cases: Covering Every Scenario for Secure Access

A login page is the first line of defense in any website or application. It’s how your users begin interacting with you—think logging in on your Facebook account or Outlook email account.

However, despite being such a familiar step in this digital age, a login page is often overlooked for thorough testing. A single broken flow or security loophole in the login process can disrupt user access, resulting in poor first impressions or data breaches.

The login page is where trust begins, from personalized dashboards to confidential information. That’s why writing robust test cases for them is an absolute necessity for testing efforts.

In this blog, we’ll walk through the different types of test cases for login pages you should know about whether you’re testing a mobile app, website, or a multi-platform system. We’ll also explore the best practices for writing these test cases. But first, a quick refresher on the basics:

Characteristics and Components of a Login Page

Even though designs vary across apps, from Gmail to mobile banking sites, the core elements of login pages remain consistent. Here are the most common components:

• Username or email ID or phone number: The first piece of information entered in the form; it could be any of these, depending on the app
• Password: A secure field that masks the user’s password
• Submit button: This initiates and confirms the authentication process (assuming the provided details are correct)
• ‘Remember Me’ checkbox: An option that allows the system to retain user credentials for future logins
• ‘Forgot Password’ link: Offers a way to reset the password in case it’s forgotten
• Two-Factor Authentication (2FA): A second verification step, such as an OTP (one-time password) sent via SMS or email
• Login with social accounts: Options to log in using third-party services like “Continue with Google” or “Login with Facebook”
• CAPTCHA or bot protection box: This prevents automated login attempts by verifying the user is a human

11 Types of Test Cases for Login Page

Here are 11 login page test cases that you can write, covering different aspects of software testing:

Functional test cases

To ensure the login functionality works exactly as intended, under both controlled and standard edge conditions, use the following test case example for login pages:

1. Login with valid/invalid credentials

Here, the goal is to confirm that a user can successfully log in with a valid username and password and to check what happens when they use invalid details.

Steps:

• Open the login page
• Enter a valid username and valid password
• Click the Login button OR press Enter
• Observe the redirection behavior

Repeat steps 1–4 with the following variations:

• Valid username, invalid password
• Invalid username, valid password
• Invalid username, invalid password

2. Session management post login

In this test case example for login pages, let’s confirm that a user session begins after login is managed securely.

Steps:

• Log in with valid credentials
• Open Dev Tools → Inspect session cookie or token
• Refresh the page; ensure the user remains logged in
• Open the app in a new tab; verify the user is still authenticated
• Close and reopen the browser; if “Remember Me” was selected, confirm the session persists

Pro Tip: Log in from two devices and see if one invalidates the other (some systems force single-session policies).

3. Password flexibility

To check your app can handle a wide variety of valid password formats, follow these steps:

• Attempt login using passwords with:
• Special characters (e.g., P@ssw0rd!)
• Spaces (e.g., My Pass word)
• Mixed casing (e.g., PaSsWoRd)
• Minimum length (e.g., 6 characters if that’s the rule)
• Maximum length (e.g., 64 characters if allowed)

Negative test cases

We’ve said this before: real-world users are random; they don’t follow any pattern while using the app. Negative testing prepares you for that.

4. SQL injection attempt

In this test case for login pages, we ensure that the login fields aren’t vulnerable to SQL injection. The server should return a generic login error without revealing technical details, and the app shouldn’t allow authorized access.

Steps:

• Open the login page
• Enter SQL injection payloads in the username or password field, such as:

OR 1=1 —
UNION SELECT null,null —
OR ‘x’=’x’

• Submit the login form

5. Disabled account login

What happens if users with suspended or deactivated accounts can’t log in? No session should be created. No token should be issued.

Steps:

• Use an admin panel or database script to deactivate a test account
• Attempt to log in using the deactivated account’s credentials
• Inspect session or token behavior after submission

UI/UX test cases

It’s essential to consider how your login page looks, feels, and behaves for the end user. Visual testing ensures that your app or site is intuitive, accessible, and consistent.

6. Responsive design

The goal here is to verify the login page adjusts gracefully across devices and screen sizes.

Steps:

• Open the login page on:

Desktop browser
Tablet device
Mobile phone (portrait + landscape)

• Rotate device orientation while on the login form
• Observe any layout shifts or input field cut-offs

7. Accessibility

Can users with disabilities interact with your login form using assistive technologies? To find out, here’s a test case example for login pages.

Steps:

• Use keyboard navigation (Tab, Shift+Tab, Enter, Space) to access and activate all interactive elements in a logical focus order
• Validate focus indicators, ARIA labels, and accessible input attributes
• Run tools like Axe or Lighthouse to detect WCAG violations
• Screen reader compatibility (try NVDA, VoiceOver)

Pro Tip: “Forgot Password” and “Sign Up” links must be reachable by keyboard and clearly announced by screen readers.

Security test cases

You want your login system to resist exploitation and ensure that users have a safe experience whenever they share their personal information. That’s why security testing is important.

8. HTTPS enforcement

Ensure all login requests and responses are securely transmitted over HTTPS.

Steps:

• Try accessing the login page via http://yourapp.com/login
• Observe if the request is redirected or blocked
• Open browser Dev Tools → Network tab and inspect request protocol

The page should automatically redirect to “https://.”

Pro Tip: Use HSTS headers to enforce secure protocol even on first access.

9. CAPTCHA integration

CAPTCHA helps detect and block bot-based login attempts.

Steps:

• Trigger CAPTCHA by:

Repeated failed logins
Logging in from a suspicious IP

• Interact with CAPTCHA (image/audio)
• Attempt login without solving the CAPTCHA
• Solve CAPTCHA and attempt to log in again

Good Practice: Don’t always show CAPTCHA. Trigger it contextually. For instance, if the system notices suspicious behavior (maybe 5 failed login attempts from the same IP address within 10 minutes), then initiate CAPTCHA.

Performance and load test cases

Is your login page on the mobile app or website stable and fast? Can it sustain itself even when users flood in? That’s what these tests help you gauge.

10. Concurrent logins

The goal is to assess how the page behaves under simultaneous login attempts. Here’s a test case example for login pages.

Steps:

• Simulate 1000+ concurrent users logging in within 1–2 minutes
• Observe response times, success/failure rates, server errors
• Monitor database load, backend CPU, and memory usage

11. Login response time

This test case comes in handy for measuring how long the login flow takes across devices and networks under normal and peak conditions.

Steps:

• Measure end-to-end response time from form submission to full dashboard render including authentication and backend processing:

On desktop
On mobile
On slow networks (e.g., 3G)

• Record performance on low-end devices and browsers

Ideal Target: Login flows should ideally respond in under 2 seconds.

Best Practices for Writing Test Cases for Login Pages

Now that you know the different test cases of login pages to focus on, the next step is writing. They should be structured with clarity, purpose, and reusability in mind. After all, that’s what determines the long-term value of test cases.

1. Draft clear and descriptive test case steps

Your test cases should be written so that anyone, a new QA hire, a developer doing a hotfix, or a non-technical stakeholder, can immediately follow them.

That’s the bar you should aim for. Use simple, consistent language and break down steps logically, no matter how small or trivial they may seem. For example, if a specific user is needed, document it. If the test case requires the user to be logged out beforehand, mention that.

Don’t assume prior knowledge. Use a short “Preconditions” section at the top of each test case so expectations are set from the start. Test cases for login pages that fail due to missing context are frustrating and time-consuming.

2. Include both positive and negative scenarios

Testing only what should happen isn’t enough. You should also cover what shouldn’t happen when writing a test case for login pages.

While positive test cases verify valid behaviors like successful logins or password resets, negative ones test how the system handles invalid inputs, attack attempts, and broken flows. By capturing both sides, you build confidence in the reliability of the login page.

3. Prioritize security-related test cases

Because your login page is a gateway to everything in your app or site, it is a prime target for malicious users. That’s why you should include test cases that directly address threats like weak password enforcement, brute-force attempts, and SQL injection.

When writing test cases for login pages, Consider session expiration, secure cookie attributes (HttpOnly, Secure, SameSite), token storage, and error message sanitization.

4. Test across devices, browsers, and screen sizes

With so many different devices, versions, and operating systems at play, you can’t assume your users will only log in to your app via Chrome on a desktop. That’s too narrow. Broaden your horizon. Consider questions like:

• What happens if a small mobile screen on Safari is used to log in?
• Do session cookies persist in Firefox the same way they do in Edge?
• How does the login page layout look on a tablet?

Your test cases should reflect the reality of your user base. This also includes accessibility—look at aspects like screen reader behavior and keyboard navigation to ensure your login is truly inclusive. Make the login pages always work for everyone.

5. Automate repetitive or data-driven test cases

Well-written test cases should identify which are good candidates for automation and which aren’t. Why spend time manually on the same flows that can be scripted once and reused across builds? Focus that energy on exploratory flows, UI glitches, and edge cases that demand hybrid testing assistance.

For example, the case for verifying login rate limits or lockout after multiple failed attempts can be automated. However, checking for localized text alignment or cultural nuances in translated versions may require human expertise. Create your test automation strategy accordingly.

Conclusion

Login pages serve as the gateway to your application—and as such, they deserve thorough, methodical, and security-conscious testing. While they may seem simple on the surface, the number of potential failure points, from UI responsiveness to backend vulnerabilities, makes them one of the most critical components in your QA strategy.

By developing detailed login page test cases across functionality, UI/UX, performance, and especially security, you can ensure a smooth, secure, and user-friendly experience across platforms and user types. Testing positive flows is important—but so is simulating negative scenarios like invalid logins, SQL injections, and session mishandling to strengthen your application’s resilience.

Incorporating both manual and automated strategies—especially for repetitive, data-driven scenarios—will make your testing more scalable and efficient over time. And don’t forget the human factor: accessibility, real-world device coverage, and user behavior are key to creating login experiences that work for everyone.

Ultimately, a robustly tested login page not only prevents bugs and breaches—it builds trust. And trust is where every successful digital journey begins.

Source: This article was originally published on TestGrid.