Operit

Operit is a calculator that does the usual well, and also what you were missing.

BASIC AND SCIENTIFIC

Write the whole sum and see the result as you type. Tap anywhere in the expression to place the cursor and fix a mistake mid-sum, without deleting back to it. Press and hold the result to copy it.

RULE OF THREE

Direct and inverse. Fill three boxes and the fourth appears, with the arithmetic spelled out below.

UNIT CONVERTER

Eleven categories: length, mass, temperature, time, data, speed and more.

FUNCTION GRAPHS

Type f(x) and watch it drawn. Pan and zoom with your fingers.

HISTORY

Your sums are kept. Bring any result back and carry on working with it.

YOUR WAY

Light or dark theme, how many decimals you want, how thousands are separated, and degrees or radians.

OPERIT PREMIUM

• Several functions at once on the same graph, with roots, maximums and minimums

• History from previous sessions

• Finance: VAT, discounts, instalments and compound interest

• Geometry: areas, perimeters and volumes

• Electronics: Ohm's law, power and resistor colour codes

• Body: body mass index, basal metabolism and ideal weight

• Algebra: equations, progressions, combinatorics, GCD and LCM

• No ads

By monthly or yearly subscription, or a one-time purchase forever.

WHAT WILL ALWAYS BE FREE

The basic calculator, the scientific one, the rule of three and the unit converter. What the app already did, it will keep doing without paying.