Test Case

What Is a Test Case & How to Write Good Test Cases – Basic Guide

What Is a Test Case?

A test case is a documented set of actions used to check if a specific part of the system works correctly. Each test case focuses on a single objective and includes clear input, steps to perform, and the expected result. Test cases help testers work consistently, avoid missing checks, and make it easy to repeat tests later.

Why Are Test Cases Important?

• Ensure coverage of requirements and functionality
• Help new testers understand what to test
• Provide a history of what has been tested
• Support defect traceability and compliance

What Should a Good Test Case Include?

• Title / Name – Short and clear (e.g. “Login with valid credentials”)
• ID – Unique identifier (e.g. TC-001)
• Preconditions – What must be ready before testing (e.g. test user account exists)
• Test Steps – Clear, numbered actions in simple language
• Expected Result – What should happen after the steps
• Test Data – Specific inputs used (usernames, prices, etc.)

How to Write Good Test Cases?

• Use simple and clear language
• One test case = one goal
• Be specific – avoid vague words like “check if it works”
• Include positive and negative scenarios
• Avoid unnecessary details but keep steps complete
• Use consistent formatting and structure

When to Create Test Cases?

• After reviewing requirements or user stories
• Before starting formal testing
• During early planning for regression or acceptance testing

Examples:

• ✅ Good: “Step 3 – Enter invalid email format ‘test_user@bloomex.ca’ and click Submit.  Expected: Error message ‘Please enter a valid email.’ appears.”
• ❌ Bad: “Step 3 – Try entering email. See what happens.”