Diet Calc

A Flask web application that turns a small set of personal measurements into educational estimates for daily energy expenditure, BMI, water intake, and macronutrient distribution.

Live demo: diet-calc.onrender.com

Why it exists

Diet Calc was developed as a university extension project connected to UN Sustainable Development Goal 3 — Good Health and Well-Being. The project applies backend development, form validation, server-side rendering, and automated calculation tests to an accessible health-education use case.

Important

Diet Calc provides general educational estimates. It does not diagnose conditions, prescribe a diet, or replace advice from a physician, registered dietitian, or other qualified health professional.

Features

• Calculates an activity-adjusted Basal Metabolic Rate estimate using the Mifflin-St Jeor equation.
• Calculates BMI and displays its corresponding category.
• Estimates daily water intake using age-based factors.
• Distributes estimated calories across protein, fat, and carbohydrates.
• Adjusts the calorie estimate for maintenance, cutting, or bulking goals.
• Validates accepted age, height, weight, activity, goal, and sex values.
• Requires no account and stores no submitted health data.
• Includes automated tests for calculation and validation behavior.

Request flow

Browser form
    -> Flask-WTF validation
    -> Person calculation model
    -> Structured summary
    -> Jinja-rendered results

Technology stack

• Python 3.12+
• Flask 3
• Flask-WTF and WTForms
• Jinja2
• Bootstrap and custom CSS
• Waitress for the production entry point
• Pytest and GitHub Actions

Running locally

git clone https://github.com/ViniOcCode/diet-calc.git
cd diet-calc
python -m venv .venv

Activate the virtual environment:

# Linux/macOS
source .venv/bin/activate

# Windows PowerShell
.venv\Scripts\Activate.ps1

Install and run:

pip install -r requirements.txt
python main.py

Open http://localhost:8080.

For deployed environments, set a strong random SECRET_KEY. Local development receives an ephemeral fallback key, so no reusable secret is stored in the repository.

Tests

pip install -r requirements-dev.txt
pytest -q

The test suite covers worked calculation examples, the public result structure, boundary validation, and rejected activity factors.

Project structure

app/
  calculator.py        Calculation and domain validation
  main/forms.py        Input fields and form validation
  main/routes.py       Flask routes and result orchestration
  templates/           Jinja pages
  static/              CSS assets
  tests/               Calculation tests
main.py                 Application entry point
config.py               Runtime configuration

Português

Sobre o projeto

O Diet Calc é uma aplicação Flask que gera estimativas educacionais de gasto energético diário, IMC, consumo de água e distribuição de macronutrientes. O projeto foi desenvolvido como atividade de extensão universitária relacionada à ODS 3 — Saúde e Bem-Estar.

[!IMPORTANT] Os resultados são estimativas gerais. A aplicação não realiza diagnósticos, não prescreve dietas e não substitui a orientação de nutricionista, médico ou outro profissional de saúde qualificado.

Funcionalidades

• Estimativa da Taxa Metabólica Basal ajustada ao nível de atividade.
• Cálculo do IMC e exibição da categoria correspondente.
• Estimativa de consumo diário de água por faixa etária.
• Distribuição de proteínas, gorduras e carboidratos.
• Ajuste para manutenção, cutting ou bulking.
• Validação dos dados aceitos e testes automatizados.
• Uso sem cadastro e sem armazenamento dos dados informados.

Executando

Crie um ambiente virtual, instale requirements.txt, execute python main.py e acesse http://localhost:8080.

Para executar os testes, instale requirements-dev.txt e rode pytest -q.