Expense Tracker

Expense Tracker is a full-stack Next.js SaaS application developed in January 2026 to help users gain complete clarity over their personal finances. It allows tracking of multiple bank accounts, physical cash, monthly spendings with date-based entries, and provides visual summaries of income, expenses, and balances. Built with Next.js, TypeScript, React, Tailwind CSS, and MongoDB, the application offers secure authentication, responsive design, real-time data synchronization, and an intuitive dashboard experience — perfect for anyone who wants simple yet powerful personal finance management.

Expense Tracker

Technology Stack

Next.jsNext.js
ReactReact
Tailwind CSSTailwind CSS
TypeScriptTypeScript
JavaScriptJavaScript
MongoDBMongoDB

Landing Page

The landing page introduces the Expense Tracker SaaS with a professional hero section, showcasing the core value of financial clarity. Users can navigate to login, registration, or dashboard (after authentication).

  • Modern and clean hero section design
  • Theme toggle support (light/dark)
  • Responsive layout for all devices
  • Clear calls-to-action for getting started
Landing Page image 1

Authentication Routes

Standard secure login and registration system, identical in flow to other projects. Users register with email and password, then log in to access the dashboard. Unauthenticated users are redirected to /login when trying to access protected routes.

  • Secure login form (/login)
  • Registration form (/register)
  • MongoDB with hashed password storage
  • Responsive authentication pages
Authentication Routes image 1
Authentication Routes image 2

Dashboard - Financial Overview

The main dashboard (/dashBoard) provides a complete overview of finances split into three panels: Bank Accounts & Cash, Monthly Overview, and Selected Month Spendings. Users can manage banks, cash, months, and daily expenses with real-time updates and persistent MongoDB storage.

  • Three-column responsive layout
  • Real-time balance calculations
  • Unsaved changes detection & save button
  • Beautiful gradient cards & modern UI
Dashboard - Financial Overview image 1

Bank Accounts Management

Users can add new banks, view current balances, and perform deposit, withdrawal, and inter-bank transfer operations through a clean modal interface. All changes are instantly reflected and saved to the database.

  • Add new bank accounts
  • Deposit / Withdraw / Transfer functionality
  • Search/filter bank accounts
  • Rich visual bank cards with gradients
Bank Accounts Management image 1

Cash Management

Dedicated cash management section allows users to track physical cash, deposit cash to banks, or record new cash earnings — all with safety checks and real-time updates.

  • Track physical cash balance
  • Deposit cash to any bank
  • Record new cash income
  • Clean modal interface for cash actions
Cash Management image 1

Monthly Spending Tracking

Users can create new months, select any month to view, and add daily spendings with date, item name, and amount. The system prevents duplicate dates and updates cash balance accordingly.

  • Add previous/next/current months
  • Monthly spending list with totals
  • Add/edit/delete daily expenses
  • Date uniqueness validation
Monthly Spending Tracking image 1
Monthly Spending Tracking image 2

Technical Implementation

Built with Next.js App Router and TypeScript for type-safe full-stack development. Uses MongoDB for persistent financial data, Tailwind CSS for responsive styling, and modern React patterns for smooth user experience.

  • Next.js App Router + TypeScript
  • MongoDB for real-time finance data
  • Optimistic UI updates & error handling
  • Responsive design with theme support