Software Requirements Specification (SRS) for Loan Affordability Calculator

Introduction

Purpose:

The purpose of this document is to define the requirements for the development of a Loan Affordability Calculator. This web-based application aims to help users determine the loan amount they can afford based on income, expenses, and the debt-to-income ratio.

Scope:

The Loan Affordability Calculator will provide users with an interface to input details such as income, expenses, and existing debts. The application will calculate and display the maximum loan amount a user can afford based on their financial information.

System Overview

System Description:

The system will be a client-server application. Users will access the Loan Affordability Calculator through a web browser. The server will handle the logic for loan affordability calculations.

System Architecture:

The application will follow a three-tier architecture: presentation layer (client-side browser), application layer (server-side processing), and data layer (storage and retrieval of data).

Functional Requirements

Use Cases:

Determine Loan Affordability:

• Users can input details such as monthly income, monthly expenses, and existing debts.
• The system will calculate and display the maximum loan amount the user can afford based on the debt-to-income ratio.

Functional Requirements:

Input:

• The system shall allow users to enter the following details:
• • Monthly Income (Decimal)
  • Monthly Expenses (Decimal)
  • Existing Debts (Decimal)

Calculation:

• The system shall calculate the maximum loan amount based on the debt-to-income ratio and user-input details.

Output:

• The system shall display the calculated maximum loan amount to the user.

External Interface Requirements

User Interfaces:

• The user interface shall consist of input fields for monthly income, monthly expenses, and existing debts, along with a “Calculate” button.
• The calculated maximum loan amount shall be displayed prominently.

Hardware Interfaces:

The system should be compatible with standard computing hardware.

Software Interfaces:

• The application will be developed using HTML, CSS, and JavaScript for the frontend.
• The backend can be implemented using a server-side framework (e.g., Node.js, Django) with a database for data storage.

Communication Interfaces:

The application will communicate with the server for loan affordability calculations.

Performance Requirements

Response Time:

The system should provide a response time of under 3 seconds for a typical user input.

 Throughput:

The application should handle at least 50 simultaneous users.

System Constraints

Regulatory Requirements:

The application should comply with relevant financial regulations.

Hardware Limitations:

The system should be compatible with devices supporting standard web browsers.

Security Requirements

Authentication:

User authentication may be implemented for personalized features.

Data Protection:

User data, if stored, should be securely protected.

Quality Attributes

Reliability:

The application should provide accurate loan affordability calculations based on the entered details.

Maintainability:

The code should be well-documented for ease of maintenance.

Usability:

The user interface should be intuitive, requiring minimal guidance.

Testing Requirements

Test Cases:

Test cases should cover various scenarios with different monthly incomes, expenses, and existing debts to ensure accurate loan affordability calculations.

Test Case 1:

• Inputs: Monthly Income = 50,000 INR, Monthly Expenses = 30,000 INR, Existing Debts = 10,000 INR.
• Expected Output: Maximum Loan Amount ≈ 5,000 INR.

Test Case 2:

• Inputs: Monthly Income = $4,000, Monthly Expenses = $2,500, Existing Debts = $1,000.
• Expected Output: Maximum Loan Amount ≈ $500.

Test Case 3:

• Inputs: Monthly Income = 40,000 INR, Monthly Expenses = 25,000 INR, Existing Debts = 8,000 INR.
• Expected Output: Maximum Loan Amount ≈ 7,000 INR.

Acceptance Criteria:

• The application is considered successful if it produces correct maximum loan amounts based on the provided details.

Project Timeline

Milestones:

Design, Development, Testing, Deployment.

Development Phases:

Frontend development, Backend development, Testing, Deployment.

Glossary

None

Database Structure

Tables:

LoanAffordability_Calculator_Records:

• RecordID (Primary Key, Auto-increment)
• UserID (Foreign Key, if user accounts are implemented)
• MonthlyIncome (Decimal)
• MonthlyExpenses (Decimal)
• ExistingDebts (Decimal)
• MaxLoanAmount (Decimal)
• CalculationDate (DateTime)

Conclusion

This SRS document outlines the requirements for the Loan Affordability Calculator. It serves as a guide for the development team and ensures that the application meets the specified criteria. Review and approval by relevant stakeholders are essential before proceeding with the development phase.