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Zenith Reckon
Math the way you think it.
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Overview
Zenith Reckon is a scratchpad calculator with units, variables, and live results. Type expressions on the left and answers appear on the right as you type — each line is one calculation, and the names and units you use carry through the whole sheet. Mix units freely, reference physical constants by name, define your own functions, and solve, differentiate, or integrate them numerically. Built for engineers, scientists, and students who reach for a calculator several times a day. Reckon docks to the side of your screen, auto-saves between sessions, and stays out of your way until you need it.
What is included
- live results as you type
- multi-line scratchpad
- persistent variables across lines
- unit-aware arithmetic
- natural unit conversion with "to" keyword
- 15 CODATA physical constants
- user-defined functions
- numerical solver
- numerical differentiation
- numerical integration
- statistics functions (mean
- median
- stdev
- variance
- mode)
- vector operations (dot
- cross
- norm)
- complex numbers with literal 2 + 3i syntax
- sums and products over functions
- full math library (trig
- log
- exp
- factorial)
- inline comments
- auto-save between sessions
- dark-mode native UI
- in-app manual
- keyboard-first interface
- cross-platform desktop app