prd.txt

# Product Requirements Document (PRD)

## 1. Product Overview

**Product Name (Working Title):** Trip Cost Split

Trip Cost Split is a simple, mobile-first web application that helps groups (friends, students, coworkers, or families) fairly split fuel costs for road trips. Users input trip and vehicle details, and the app instantly calculates the total fuel cost and an equal per-person split. The output is formatted as clean, copyable text that can be shared via WhatsApp, text messages, or any chat app.

The product focuses on **speed, clarity, and shareability**, with zero friction to use.

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## 2. Goals & Objectives

### Primary Goals

* Allow users to calculate trip fuel costs quickly and accurately
* Provide a fair and transparent cost split among travelers
* Enable easy sharing of results as plain text

### Success Metrics

* Time to first calculation < 30 seconds
* High copy/share usage (Copy button clicks)
* Low bounce rate on mobile devices

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## 3. Target Users

### Primary Users

* Friends going on road trips
* College students sharing rides
* Office colleagues carpooling

### Secondary Users

* Ride owners who want to explain costs clearly
* Budget-conscious travelers

User traits:

* Mobile-first
* Non-technical
* Wants quick answers, not complex setup

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## 4. User Problem

Users currently:

* Manually calculate fuel costs using rough estimates
* Argue or feel awkward about “who owes how much”
* Lack a clean, neutral format to share cost breakdowns

**Problem Statement:**

> There is no fast, simple, and shareable way to fairly split fuel costs for trips.

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## 5. Core Features (MVP)

### 5.1 Trip Input Form

Users can input:

* Distance (km)
* Vehicle mileage (km/l)
* Fuel price (₹/l)
* Number of people in vehicle (including owner)

All fields are:

* User-editable
* Required
* Validated (no negative or zero values)

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### 5.2 Cost Calculation Logic

**Formula:**

* Fuel Required = Distance / Mileage
* Total Cost = Fuel Required × Fuel Price
* Per Person Cost = Total Cost / Number of People

Rounding:

* Total cost shown with 1 decimal
* Per person cost rounded to nearest whole number

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### 5.3 Results Display

Displayed clearly below the form:

* Total Cost
* Distance
* Mileage
* Fuel Price
* Number of People
* Per-person contribution

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### 5.4 Copyable Share Text (Key Feature)

A pre-formatted, selectable text block:

```
TRIP COST SPLIT
---------------
Total Cost: ₹322.2
Distance: 120 km
Mileage: 40 km/l
Fuel Price: ₹107.4/l
People: 3

SPLIT:
Each person pays: ₹107
(3 people paying including owner)
```

Includes:

* One-tap **Copy to Clipboard** button
* Optimized for WhatsApp & SMS sharing

---

## 6. User Flow

1. User lands on homepage
2. Enters trip details
3. Clicks “Calculate” (or auto-calculates)
4. Sees cost breakdown
5. Copies and shares result

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## 7. UX & UI Requirements

### Design Principles

* Minimal
* Friendly
* Neutral (no judgment, no ownership bias)

### Styling (Reference-Based)

* Background: Cream (`bg-cream`)
* Text color: Ink (`text-ink`)
* Font:

  * Body: Inter
  * Monospace sections: Aeonik Mono / Space Mono
* Layout:

  * Centered column layout
  * Mobile-first
  * Max-width container on desktop

### Interaction

* Instant feedback on input changes
* No page reloads
* Accessible tap targets

---

## 8. Technical Requirements

### Frontend

* HTML + CSS (Tailwind-style utility classes)
* JavaScript for calculations & clipboard
* Fully responsive

### No Backend Required (MVP)

* All calculations run client-side
* No authentication
* No data storage

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## 9. Edge Cases & Validation

* Mileage cannot be zero
* Number of people must be ≥ 1
* Fuel price must be positive
* Large distances handled gracefully

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## 10. Future Enhancements (Post-MVP)

* Multiple vehicles support
* Split excluding owner
* Currency selector
* Save/share via link
* PWA (offline support)
* Expense history

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## 11. Out of Scope (MVP)

* Payments
* User accounts
* Trip history
* Maps & routing

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## 12. Launch Criteria

* Accurate calculations
* Works on major mobile browsers
* Copy feature works reliably
* Clear UI with no instructions needed

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**This PRD defines a focused, high-utility MVP designed for rapid adoption and everyday use.**