One app for the three conversions you actually need — travelling, working, studying.
CURRENCY
• 166 currencies, updated daily
• See one amount in several currencies at once, updating live
• Type an expression straight into the amount field: 1250×3 converts 3750
• Rates from open.er-api.com, with the European Central Bank as backup
• Cached on device, so the last rates still work with no connection
UNITS
15 categories, 224 units: length, weight, volume, area, speed, time, temperature, pressure, power, energy, data, density, angle, force, electricity.
Includes units other converters skip — Taiwanese ping, jia, chi and jin, Chinese shi jin and shi mu, troy ounces, US dry and liquid measures kept properly separate. Temperature uses real formulas, not a ratio.
ENGINEERING CALCULATOR
Switch between basic and engineering mode. Engineering mode has five pages:
• Functions: x^y, √, ∛, ⁿ√, |x|, n!, e^x, ln, log, log₂, mod, floor, ceil
• Trig: sin/cos/tan, inverse, hyperbolic, inverse hyperbolic, degrees or radians
• Discrete: nPr, nCr, gcd, lcm, AND/OR/XOR/NOT, bit shifts
• Analysis: Σ series, Π product, derivative d/dx, definite integral ∫, mean, median, standard deviation, variance
• Constants: π, τ, e, φ, plus 15 physical constants including the speed of light, Planck constant and Avogadro number
Derivatives use central differences and integrals use adaptive Simpson — not lookup approximations. Bitwise results show hex, octal and binary side by side, with negatives in two's complement. Memory keys M+ / M− / MR / MC included.
MORE
• 20 languages, with currency names and number formats following your region
• Dark mode
• No sign-up, no account
Privacy: no personal data collected. The amounts and expressions you type never leave your device.
