Three (Rule of 3 Calculator) app icon

Apps Like Three (Rule of 3 Calculator) for iPhone and iPad

Calculate anything with the rule of three.

The app performs fast calculations using the rule of three. It offers a modern interface with options for displaying results, including thousands separators and decimal digits.

by Pericles Maravelakis★ 5.02 ratingsUtilitiesFreeData updated 2026-10-18

Three (Rule of 3 Calculator) screenshots

Ranked alternatives

Showing 1–20 of 1,000 ranked alternatives.

  1. Calculator with History + app icon

    Calculator with History +

    Beijing Free Calculator Technology Co., Ltd.

    Calculate and track financial formulas

    Perform calculations a scientific featuring pi, exponents, square root, negative numbers, and logarithms. View calculation and adjust decimal places or use thousands separators. Customize keyboard colors and sounds.

    ★ 4.725,089 ratingsFinanceFreeData updated 2026-09-17
  2. Fuel Calculator app icon

    Fuel Calculator

    George Richardson

    Calculate car journey prices quickly and easily.

    The app calculates car journey prices using distance, fuel cost, and fuel consumption. It supports various units for distance, fuel cost, and fuel economy, which can be adjusted in settings.

    ★ 3.02 ratingsUtilitiesFreeData updated 2026-11-07
  3. Calculator - Pad Edition app icon

    Calculator - Pad Edition

    Ratha Sou

    Calculate in portrait, science in landscape

    Perform basic calculations in portrait mode and scientific calculations in landscape. Use root, power, factorial, exponential, division, logarithm, and trigonometric functions. Features a flat UI design similar to built-in iOS apps.

    ★ 4.7357,788 ratingsUtilitiesFreeData updated 2026-09-08
  1. Calculator₊ app icon

    Calculator₊

    Impala Studios B.V.

    Calculate, edit, and track equations

    Perform basic arithmetic operations including addition, subtraction, multiplication, and division. Access scientific functions for advanced calculations. Convert units between different measurement systems.

    ★ 4.71,729,318 ratingsUtilitiesFreeData updated 2026-09-08
  2. Calculator⁼ app icon

    Calculator⁼

    Impala Studios B.V.

    Calculate, edit, and track results

    Calculator provides basic and scientific calculation functions. Users can access a history of past calculations for review or reuse. It includes a live currency converter for exchange rate checks.

    ★ 4.6358,634 ratingsUtilitiesFreeData updated 2026-09-08
  3. Basic Calculator: Classic Calc app icon

    Basic Calculator: Classic Calc

    MobArts Ltd

    Calculate, split, and customize

    Perform general calculations including addition, subtraction, multiplication, division, and square roots. Use memory functions for storage and retrieval. Apply thousands separators and handle numbers up to 60 digits.

    ★ 4.83,214 ratingsUtilitiesFreeData updated 2026-09-08
  4. Calculator with History Tape app icon

    Calculator with History Tape

    帆 杨

    Calculate, record, and customize equations

    A a log of all calculations. Displays input equations and results clearly. Includes backspace function. Allows adjustable keyboard size and number font size. Supports customization of decimal places, font size for , and display format.

    ★ 4.73,210 ratingsProductivityFreeData updated 2026-09-17
  5. Acc Calculator app icon

    Acc Calculator

    Digital Mind Co., Ltd.

    Basic calculations with paper tape

    The app provides basic arithmetic calculations with a two-line display and a paper tape. It shows the calculation formula and its result simultaneously, featuring large buttons for ease of use.

    ★ 4.7133 ratingsUtilities$0.99Data updated 2026-09-19
  6. Calculator‰ app icon

    Calculator‰

    Tim O's Studios, LLC

    Calculate with large buttons and clear display

    A calculator with large buttons and a clear display for efficient calculations. Supports basic arithmetic operations. Includes a Retina Display for improved visibility.

    ★ 4.9409,196 ratingsUtilitiesFreeData updated 2026-09-08
  7. Euros To US Dollars app icon

    Euros To US Dollars

    Armchair Engineering

    Convert currency with real-time rates

    Convert currencies between (EUR) and US (USD) using real-time exchange rates. Choose the number of decimal places for precision. Perform quick conversions without additional steps.

    ★ 4.884 ratingsUtilities$1.99Data updated 2026-09-10
  8. Dilution Calculator app icon

    Dilution Calculator

    Samuel Blackburn

    Calculate ratios instantly

    Calculate ratios by entering the desired ratio and bottle size. Determine the exact amounts of water and solution needed. Supports litres and millimetres with future unit additions. Share results or provide feedback through in- options.

    ★ 4.7156 ratingsUtilitiesFreeData updated 2026-09-25
  9. Calculator for iPad₊ app icon

    Calculator for iPad₊

    Impala Studios B.V.

    Calculate and share equations instantly

    Perform complex mathematical calculations using scientific functions and simple arithmetic. Calculate percentages, taxes, and financial figures. Save and share results with others. Syncs with iPad and iPhone.

    ★ 4.5126,019 ratingsUtilitiesFreeData updated 2026-09-11
  10. Distances To app icon

    Distances To

    Danny Pajevic

    Calculate and fuel costs

    Calculate driving , flight , and fuel costs between locations. View travel time and elevation data. Convert results to miles, kilometers, meters, or feet. Find coordinates in DMS or decimal format. Display road maps for routes.

    ★ 4.3886 ratingsUtilitiesFreeData updated 2026-09-09
  11. Simple Calculator. + app icon

    Simple Calculator. +

    tasser gyati

    Calculate taxes and percentages

    Perform arithmetic calculations with 12 digits. Calculate tax, percentages, and cost, selling price, and gross margin. Use memory functions, square root, and sign change. Track grand total.

    ★ 4.7147 ratingsUtilities$1.99Data updated 2026-09-14
  12. Mexican Pesos To US Dollars app icon

    Mexican Pesos To US Dollars

    Armchair Engineering

    Convert MXN to USD with precision

    Convert using real-time exchange rates. Choose the number of decimal places for precision. Input amounts and view converted values instantly.

    ★ 4.8769 ratingsUtilities$1.99Data updated 2026-10-14
  13. Scientific Calculator Plus 991 app icon

    Scientific Calculator Plus 991

    Tran Duy

    Calculate, graph, convert, solve

    Allows users to perform complex calculations with a natural display that shows expressions as written. It supports fractions, roots, and exponents. The includes a graphing module for visualizing equations.

    ★ 4.712,406 ratingsEducationFreeData updated 2026-09-16
  14. Calculator HD Pro Lite app icon

    Calculator HD Pro Lite

    Cider Software LLC

    Calculate with dual-line display and multi-line input

    A with dual-line display showing input and result. Supports multi-line equations and tap-to-move cursor. Saves calculation history with timestamps and labels. Allows emailing calculations and swiping to review previous entries.

    ★ 4.651,412 ratingsUtilitiesFreeData updated 2026-09-08
  15. Financial Calculator: Percent app icon

    Financial Calculator: Percent

    Applorium Ltd

    Calculate interest, taxes, and averages

    Calculate metrics with 25+ built-in tools including average share price, tax, interest, profit, markup, discount, mortgage, tip, ROI, IRR, and CAGR. Perform investment analysis and everyday percentage calculations.

    ★ 4.714,729 ratingsFinanceFreeData updated 2026-09-09
  16. Fraction Calculator Plus #1 app icon

    Fraction Calculator Plus #1

    DigitAlchemy LLC

    Calculate fractions, add, subtract, divide, multiply, convert

    Calculate fractions with addition, subtraction, multiplication, and division. Convert fractions to decimals. Adjust recipe quantities for different serving sizes. Review math problems and convert measurements between cups and teaspoons.

    ★ 4.922,272 ratingsProductivityFreeData updated 2026-09-08
  17. ▸ Calculator + app icon

    ▸ Calculator +

    CAT VIET SOFTWARE DEVELOPMENT & MEDIA JSC

    Calculate, convert, and solve equations

    Perform complex calculations using 12 built-in calculators including scientific, financial, and unit conversion tools. Input formulas with three modes: standard, string, and RPN.

    ★ 4.7899 ratingsUtilities$1.99Data updated 2026-09-08

How we rank alternatives

Apps are ranked by functional similarity, category fit, rating confidence, and popularity.