X-Calculator app icon X-Calculator for iPhone & iPad

One calculator for
every kind of calculation.

From everyday arithmetic to engineering formulas and professional financial analysis — eight calculator modes in one native iOS app. Money is computed in exact decimal arithmetic, never floating point. Fully offline: no account, no analytics, no ads, no network access at all.

Coming soon to the App Store

Eight modes, one engine

Simple & Scientific

Everyday arithmetic with memory keys, undo/redo and live preview — plus trig, logs, powers, constants, DEG/RAD/GRAD and a 2nd-function layer. Errors are named and positioned, never NaN.

Engineering

Solve-for-the-unknown forms in SI units: Ohm's law, electrical power, series/parallel resistance, frequency ↔ wavelength, force, pressure, energy, torque and fluid flow.

💰

Financial

15 calculators — EMI with full amortisation schedule (CSV & PDF export), SIP with step-up, FV/PV, CAGR, NPV/IRR/XIRR, retirement, inflation and more. Every result shows its assumptions.

🔢

Programmer & Statistics

BIN / OCT / HEX with bitwise operations, and descriptive statistics — mean, median, mode, quartiles, variance — from any pasted data list.

📅

Date & Time + Conversion

Date differences, business days, and unit conversion across length, mass, temperature and more.

🔒

Private by design

No account, no analytics, no network code. History and settings stay on your device — export or delete them any time.

Built for correctness

Money is decimal, never binary floating point. Rounding policies are explicit — half-up, bankers', toward −∞ or +∞ — and every financial result lists the compounding, timing and day-count conventions it used. The calculation core is covered by unit tests against published reference values.