A web-based Reverse Polish Notation (RPN) calculator inspired by the legendary HP-67 calculator.
- 4-level stack (T, Z, Y, X registers) for efficient chain calculations
- ENTER key to push values onto the stack
- Stack manipulation functions: SWAP (x⇄y), ROLL (R↓), DUP, DROP
- LAST x to recall the last X register value
- Trigonometric: SIN, COS, TAN, ASIN, ACOS, ATAN
- Logarithmic: LN (natural log), LOG (base-10), e^x
- Power functions: x², √x, y^x, 1/x
- Other math: |x| (absolute value), INT, FRAC, π, %, x! (factorial)
- →P (rectangular to polar): converts (x, y) to (r, θ)
- →R (polar to rectangular): converts (r, θ) to (x, y)
- →H.MS: converts decimal hours to H.MS format
- STO/RCL: Store and recall values from memory
- Σ+: Add data points for statistical calculations
- x̄ (mean): Calculate average of stored data points
- s (standard deviation): Calculate sample standard deviation
- L.R.: Linear regression (returns slope and intercept)
- Standard numeric entry with decimal point
- CHS: Change sign (negate current value)
- EEX: Enter scientific notation exponent
- DEL: Delete current entry
- CLR: Clear all stack registers
- Mouse/Touch: Click buttons to operate
- Keyboard shortcuts:
- Numbers 0-9 and decimal point
- Enter key for ENTER
- Backspace for DEL
- Escape for CLR
To calculate 5 + 3:
- Enter
5 - Press
ENTER - Enter
3 - Press
+ - Result:
8
The RPN stack allows you to work with multiple values efficiently:
- X register: Current/display value
- Y register: Second value for operations
- Z register: Third stack level
- T register: Top of stack (automatically duplicates when needed)
- Pure HTML5, CSS3, and vanilla JavaScript
- No external dependencies or frameworks
- Responsive design works on desktop and mobile
Simply open index.html in any modern web browser.
Unrestricted public domain - feel free to use and modify!