226+ iOS apps curated and reviewed
Out of 226+ btu calculator apps on iOS, 17 are free and the rest sit in the paid tier. This page sorts them so you can compare both sides before you commit.
| # | App | Price | Rating | Ads | In-App Purchases | Updated |
|---|---|---|---|---|---|---|
| 1 |  | Free | — | Yes | No | Jul 2026 |
| 2 |  | Free | 4.6★ (288) | Yes | Yes | Jul 2026 |
| 3 |  | Free | 5.0★ (5) | No | No | May 2026 |
| 4 |  | Free | 5.0★ (5) | Yes | Yes | May 2026 |
| 5 |  | Free | 4.8★ (20) | No | Yes | May 2026 |
| 6 |  | Free | — | No | No | Jun 2026 |
| 7 |  | Free | 4.0★ (8) | No | Yes | May 2026 |
| 8 |  | $5.99 | 4.7★ (6.2K) | No | Yes | Jul 2026 |
Estimate the cooling capacity needed for your data center. This tool considers factors like space, occupants, and heat output to help you maintain optimal temperature and humidity. It provides instant results as you update inputs, serving as a guide for system selection.
This utility helps you determine the appropriate cooling capacity for an air conditioner based on room size and other factors. It simplifies the process of selecting the right unit to ensure optimal comfort and energy efficiency.
This tool helps you calculate the right size for air conditioners, heat pumps, and furnaces. It provides detailed analysis of heating and cooling costs, energy consumption, and temperature data. You can also evaluate domestic hot water needs and financial aspects like payback periods.
This utility app simplifies HVAC sizing by calculating BTU/h capacity and recommending equipment. It offers unit conversions, price estimates, and energy consumption comparisons. Advanced features can be unlocked via in-app purchases.
This tool provides HVAC technicians with instant access to pressure and temperature data for over 100 refrigerants. It allows users to input one value to find the other, view detailed refrigerant properties, and email comprehensive charts and data.
This advanced calculator app offers a powerful math core and algebra engine for basic to complex calculations. It includes features like step-by-step solutions, handwriting recognition, and 2D graphing, making it suitable for students, engineers, and programmers.
This multi-function calculator offers basic to advanced scientific and algebraic computations. It includes features like handwriting recognition, equation solvers, and 2D graphing, making it suitable for students and professionals. In-app purchases unlock advanced capabilities.
This comprehensive calculator app offers a wide range of tools for everyday calculations, from basic arithmetic and scientific functions to unit and currency conversions. It includes specialized calculators for loans, health, fuel costs, GPA, and more, all within a clean and user-friendly interface.
This free calculator app offers a fast, ad-free experience with a visual input and calculation history. Customize your experience with various keyboard sounds and colors, and access advanced scientific functions when needed.
This app offers both basic and scientific calculation modes with over 30 scientific operations. It allows for customization of the app's appearance and includes features for note-taking, drawing, and viewing calculation history. It supports high accuracy calculations and nested parentheses.
This app offers a comprehensive suite of over 40 calculators and unit converters for various needs, including finance, health, construction, and everyday math. It features standard, scientific, and specialized calculators for tasks like loan amortization, currency conversion, and material estimation.
This app is a powerful scientific calculator with graphing capabilities, a formula library, and a unit converter. It offers natural display input, advanced math functions for algebra, calculus, and statistics, and supports various number bases and formats.
Emulates the TI BAII Plus financial calculator, offering identical functionality with a clean and user-friendly interface. It's designed for finance professionals and students preparing for exams like CFA, FRM, and CPA.
This app functions as a scientific calculator, enabling users to input and edit complex formulas with ease. It supports formula history, variable memory, and various number system conversions for accurate calculations.
This app provides a straightforward calculator experience with a comprehensive history log of all your computations. Customize the keyboard, display, and history records to suit your needs. Easily add annotations and titles to past calculations for better organization.
This app offers a powerful graphing calculator experience with touch-based input for enhanced interaction. It supports natural textbook notation, advanced math functions, and various plotting capabilities. Users can also utilize its programming features and built-in tools like unit conversion and a periodic table.
This app offers a versatile calculator with three distinct modes: Basic, Scientific, and Programmer. It provides a history view, sharing capabilities, and supports various input and output formats. The app is designed for iPhone, iPad, and iPod Touch.
This app offers a comprehensive financial calculator with over 105 functions for business, statistics, and general math. It simplifies complex calculations like loan payments, time value of money, and investment analysis with an intuitive interface and visual tools. Easy modes are available for users new to financial calculations.