Working with Money in PHP: The Value Object Approach

Financial software requires exact monetary calculations, but PHP's floating-point arithmetic (IEEE 754) introduces precision errors that accumulate into significant discrepancies across transactions, payroll, and taxes. The industry-standard solution, used by banks and payment processors like Stripe and PayPal, is to store money as integers in the smallest currency unit (cents) and use proper rounding during conversion. A Value Object approach in PHP encapsulates this pattern, ensuring precision, portability, and performance across all currencies.