bd_money_formatter: Format Numbers in Bangladesh Money Style with Dart

Bangladesh uses a unique number grouping system for currency that is different from the international standard. Instead of 1,234,567, Bangladeshi format writes it as 12,34,567 — the rightmost group has 3 digits, and every subsequent group has 2 digits. The bd_money_formatter package handles this formatting correctly with a simple API and convenient extension methods.

The Bangladesh Money Format

Most countries use groups of three digits separated by commas:

International: 1,234,567

Bangladesh follows the South Asian numbering system where only the first group (from the right) has three digits, and all subsequent groups have two:

Bangladesh: 12,34,567

Here is how different values look in BD format:

| Number | International | Bangladesh | |--------|--------------|------------| | 1000 | 1,000 | 1,000 | | 50000 | 50,000 | 50,000 | | 100000 | 100,000 | 1,00,000 | | 1234567 | 1,234,567 | 12,34,567 | | 2554413646 | 2,554,413,646 | 2,55,44,13,646 |

Installation

dependencies:
  bd_money_formatter: ^2.0.0

This is a pure Dart package with zero dependencies. It works with Flutter, server-side Dart, and CLI applications.

Quick Start with Extension Methods

The easiest way to use the package is through the extension methods on num:

import 'package:bd_money_formatter/bd_money_formatter.dart';

// Format without currency
1234567.toBDMoney();
// "12,34,567"

// Format with currency symbol (default: ৳)
1234567.toBDMoneyWithCurrency();
// "৳ 12,34,567"

// Custom currency symbol
1234567.toBDMoneyWithCurrency(currencySymbol: 'BDT');
// "BDT 12,34,567"

Handling Different Number Types

The package works with both integers and doubles:

// Integer
1234567.toBDMoney();
// "12,34,567"

// Double with decimals
97865466.352.toBDMoney();
// "9,78,65,466.352"

// Negative numbers
(-456978.32).toBDMoney();
// "-4,56,978.32"

Class-Based API

For more control, use the BDMoneyFormatter class directly:

final formatter = BDMoneyFormatter(2554413646);

// Formatted amount
print(formatter.result.amount);
// "2,55,44,13,646"

// With currency symbol
print(formatter.result.amountWithCurrency);
// "৳ 2,55,44,13,646"

// Original value
print(formatter.result.originalValue);
// 2554413646

You can also pass a custom currency symbol to the constructor:

final formatter = BDMoneyFormatter(1234567, currencySymbol: 'USD');

print(formatter.result.amountWithCurrency);
// "USD 12,34,567"

Real-World Example: Product Price Display

Here is a practical Flutter example for displaying prices in BD format:

class PriceTag extends StatelessWidget {
  final double price;
  final double? originalPrice;

  const PriceTag({required this.price, this.originalPrice});

  @override
  Widget build(BuildContext context) {
    return Row(
      children: [
        Text(
          price.toBDMoneyWithCurrency(),
          style: TextStyle(
            fontSize: 20,
            fontWeight: FontWeight.bold,
            color: Colors.green[700],
          ),
        ),
        if (originalPrice != null) ...[
          SizedBox(width: 8),
          Text(
            originalPrice!.toBDMoneyWithCurrency(),
            style: TextStyle(
              fontSize: 14,
              color: Colors.grey,
              decoration: TextDecoration.lineThrough,
            ),
          ),
        ],
      ],
    );
  }
}

// Usage
PriceTag(price: 125000, originalPrice: 150000)
// Displays: ৳ 1,25,000  ৳ 1,50,000 (strikethrough)

Example: Transaction Summary

class TransactionSummary extends StatelessWidget {
  final List<double> amounts;

  const TransactionSummary({required this.amounts});

  @override
  Widget build(BuildContext context) {
    final total = amounts.reduce((a, b) => a + b);

    return Card(
      child: Padding(
        padding: EdgeInsets.all(16),
        child: Column(
          children: [
            ...amounts.map((amount) => Padding(
              padding: EdgeInsets.symmetric(vertical: 4),
              child: Row(
                mainAxisAlignment: MainAxisAlignment.spaceBetween,
                children: [
                  Text('Item'),
                  Text(amount.toBDMoneyWithCurrency()),
                ],
              ),
            )),
            Divider(),
            Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                Text('Total', style: TextStyle(fontWeight: FontWeight.bold)),
                Text(
                  total.toBDMoneyWithCurrency(),
                  style: TextStyle(fontWeight: FontWeight.bold),
                ),
              ],
            ),
          ],
        ),
      ),
    );
  }
}

API Reference

Extension Methods on num

| Method | Description | Example | |--------|-------------|---------| | toBDMoney() | Format in BD style | 1234567.toBDMoney() → "12,34,567" | | toBDMoneyWithCurrency() | Format with ৳ symbol | 1234567.toBDMoneyWithCurrency() → "৳ 12,34,567" |

BDMoneyFormatter Class

| Property | Description | |----------|-------------| | result.amount | Formatted number string | | result.amountWithCurrency | Formatted with currency symbol | | result.originalValue | Original input value |

Summary

The bd_money_formatter package is a must-have for any Flutter or Dart application dealing with Bangladeshi currency. The extension methods make it incredibly easy to format prices, transaction amounts, and financial data in the correct BD format with just one method call.

Get it on pub.dev or view the source on GitHub.