MathDeck is an all-in-one calculator and converter for Android. It brings 90+ calculators and converters together in one fast, private app — from everyday math and a scientific calculator to unit and currency converters, graphs, finance, engineering, health, and more. No sign-up. No ads. No tracking.

Most tools work fully offline. The only time MathDeck goes online is to refresh live currency rates, and only when you open the Currency converter. Your calculations, tasks, and settings stay on your device.

ALL-IN-ONE CALCULATOR
- Basic — everyday arithmetic, percentages, and memory keys.
- Scientific — trigonometry, logarithms, exponentials, factorials, radians/degrees.
- Math & Statistics — mean, median, standard deviation, probability, percentages, weighted average, and GPA.

CONVERTERS
- Unit Converter — length, weight, temperature, area, volume, speed, data, and time.
- Currency Converter — live USD-based exchange rates for 30+ currencies (EUR, GBP, JPY, INR, AED, and more).

FINANCE & BUSINESS
- Accounting — loan EMI, compound & simple interest, amortization, mortgage, SIP, ROI, future value, depreciation, break-even, discounts.
- Business — income tax, net pay, hourly-to-annual, salary comparison, cash flow, capital gains, and business valuation.

ENGINEERING & SCIENCE
- Physics — kinematics, energy, projectile motion, waves, torque, circular motion, and optics.
- Electrical — Ohm's law, power triangle, resistor color codes, wire sizing, three-phase power, and transformers.
- Civil — concrete volume, beam bending, steel bar weight, brick estimation, slab thickness, and paint coverage.

GRAPHS & SHAPES
- Graph Plotter — visualize sin(x), cos(x), tan(x), and your own functions with an adjustable range.
- 3D Shapes — volume and surface area for 19 solids, from cube and sphere to torus, pyramid, and prisms.

EVERYDAY TOOLS
- Date & Time — age, date difference, add/subtract dates, time-zone conversion.
- Health & Fitness — BMI, calorie/TDEE, body fat, macros, heart rate zones, water intake, ideal weight.

BUILT FOR DAILY USE
- Calculation history with per-mode filtering.
- Home-screen widgets — jump straight into a calculator, or see and add today's tasks.
- Fast search to reach any of the 90+ tools in a tap.
- Three profiles — Pro (everything), Simple (the basics), or Custom (pick your own set).
- A simple built-in Tasks list with a per-task timer to help you stay focused.
- Light and dark themes with a retro 7-segment LCD display.

PRIVATE BY DESIGN
MathDeck has no accounts, no analytics, no ad SDKs, and no tracking libraries. Everything is stored locally on your device. The only network request is an anonymous call to a public exchange-rate service when you use the Currency converter.

Privacy policy: https://sites.google.com/view/mathdeck-app/privacy

MathDeck is made for students, teachers, engineers, accountants, and anyone who wants one reliable calculator and converter instead of ten separate apps.

Download MathDeck and keep your calculators, converters, graphs, and tools in one private, offline-first app.