A cross-platform carbon calculator that turns "I should cut my emissions" into a daily habit.
Log your daily CO₂e in seconds, work through guided low-carbon actions, earn badges, and ask a built-in AI assistant for tips — built with Flutter + Firebase for iOS and web.
English | 繁體中文
 Home |
 Actions |
 AI Chat |
 Social |
Most people want to lower their carbon footprint but have no easy way to measure it — looking up emission factors by hand is tedious, so they never start.
Carbon-Calculation removes that friction. Five tabs — Social, Home, Actions, Achievement, Profile — take you from measuring your footprint to reducing it: log activities, watch your CO₂e on a calendar, and work through curated actions across diet, home, office, and outdoor. The AI assistant turns plain language into an emissions estimate, while badges and a leaderboard keep the habit going.
- Carbon calculator — estimate personal CO₂e and visualise it with
fl_chart/ Syncfusion charts. - Guided actions — diet / home / office / outdoor categories, each with lists, tiles, and detail views.
- AI assistant — in-app chat powered by a fine-tuned OpenAI GPT-3.5 model.
- Gamification — badges, achievements, a points shop, and coupons.
- Social feed — posts, likes, comments, friends, and a carbon leaderboard.
- Multi-provider auth — email, Google, Apple, GitHub, and anonymous sign-in via Firebase Auth.
- Admin console — dashboard, member management, post moderation, and shop management.
- Cross-platform — one Flutter codebase shipping to iOS and the web.
Final-year university capstone · team of 5
I owned these modules end-to-end:
- Authentication (
lib/auth,lib/login) — multi-provider sign-in: email, Google, Apple, GitHub, and anonymous, via Firebase Auth. - Home calendar (
lib/pages/home) — the daily calendar that logs and tallies each day's CO₂e. - Carbon calculator (
lib/pages/calculator) — the simple footprint calculator. - Rewards (
lib/personalpage/shop,lib/flutter_flow/coupon_page.dart) — the points shop and coupon system.
- Log in seconds, not spreadsheets — tell the AI assistant "drove 50 km, ate 1 kg of beef, used 3 kWh" and get your CO₂e back instantly, with no emission-factor lookup.
- One-tap actions — four curated categories turn "cut my carbon" into concrete, loggable steps.
- See your trend — a calendar view tracks daily CO₂e, so progress and spikes are clear at a glance.
- Stay motivated — badges, achievements, and a friends leaderboard keep the habit going.
Flutter (Dart 3) · Firebase (Auth · Firestore · Storage · Cloud Functions) · OpenAI GPT-3.5 (fine-tuned) · built with FlutterFlow · go_router · provider · fl_chart / Syncfusion charts.
The Flutter client (iOS + web) uses Firebase for authentication, data (Firestore), and file storage. AI requests never call OpenAI directly: the app sends the user's Firebase ID token to a Cloud Function (chatCompletion), which verifies it and proxies the request with a server-side key — so no API secret ships inside the client.
Flutter app ──► Firebase Auth / Firestore / Storage
│
└── Firebase ID token ──► Cloud Function (chatCompletion) ──► OpenAI API
verifies token, injects key
CO2e/
├── lib/
│ ├── main.dart # app entry, Firebase init, root nav
│ ├── auth/ # Firebase auth (email/google/apple/github/anon)
│ ├── backend/ # Firestore schema, Storage, API calls
│ ├── pages/ # core feature screens
│ │ ├── home/ social/ achievement/ calculator/
│ │ ├── action/ # actions + diet/house/office/outdoor options
│ │ └── badge/ # badges & unlock flow
│ ├── chatgpt/ # in-app AI assistant
│ ├── admin_home/ # admin dashboard / members / posts / shop
│ ├── personalpage/ # profile, edit, friends, shop, help
│ └── flutter_flow/ # FlutterFlow theme, widgets, nav, shop/cart
├── firebase/ # Firestore rules/indexes, Storage rules, Functions
│ └── functions/ # onUserDeleted + chatCompletion (OpenAI proxy)
├── ios/ · web/ · test/
└── pubspec.yaml
poweichen00 — GitHub · Project repository
Released under the MIT License. Carbon-emission factors and third-party icon assets retain their original licenses.