Modern RPN

Modern RPN is a minimalist reverse polish notation calculator for iPhone and iPad, with Standard, Binary, and Hex modes for fast everyday math and programmer-friendly conversions.

Use a clean 4-level stack, instant mode switching, calculation history, and saved session state to move quickly without clutter.

Features: • True RPN input with ENTER to push or duplicate values • Standard, Binary, Financial, and Hex calculator modes • Mode-aware entry and display formatting • 4-level visible stack: T, Z, Y, X • Core operations: add, subtract, multiply, divide • Stack tools: POP, X/Y swap, sign toggle, backspace, and all clear • Calculation history with timestamps • History filtering by All, Standard, Binary, Financial, or Hex • Saved session state for your current mode, stack, and in-progress input • Clean dark interface designed for focus and readability • No accounts, no ads, no data collection

Modern RPN is designed for people who want the speed of a classic RPN calculator with a modern iOS interface.