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Scientific Calculator fx-991

Scientific Calculator fx-991

Step-by-step Math Solver

391 ratings
66 reviews
With Ads
📚 Education
Free
In-App PurchasesWith Ads

Price history

Details

  • Released
  • Updated
  • February 28, 2023
  • August 21, 2026

Features

Developer

Dinh Phuc
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About

This app provides a powerful scientific calculator with step-by-step solutions for equations, advanced functions, and graphing capabilities. It includes a formula library and unit converter, inspired by a popular Casio model, to aid in learning and problem-solving for math and science subjects.

✓Step-by-step equation solver
✓Advanced scientific functions
✓Graphing mode
✓Formula library
✓Unit converter
✓Casio fx-991 inspired interface
Show original description
+1

What's New in Scientific Calculator fx

1.9.0

August 21, 2026

◆ Enhanced derivative feature: now supports finding the derivative expression of a function, in addition to calculating the derivative value at a specific point. ◆ Performance improvements and bug fixes.

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Subscription plans

Monthly Premium Access

Full access to premium features for one month

$1.991 Month
How to cancel Scientific Calculator fx subscription ⁉️
2

In-App Purchases

$0.99

Remove Ads 30 Days

Remove ads for 30 days.

User reviews

Most RecentHighest RatedLowest Rated

Very useful and no problems with this app 🙂

I can’t think of any bad things about this app and I also love how it has imaginary numbers like i
Henry FreebornHenry Freeborn

Response from developer

We truly appreciate your support! 🙌 Your 5-star rating means a lot to us. Keep enjoying HiEdu, and don’t forget to recommend it to your friends! 🎉

I love this, good stuff ☝️🤓

I love this, good stuff ☝️🤓
LlantathLlantath

Response from developer

Amazing! Thank you for the 5-star review! 💖 We are so happy to know that you are satisfied with the app. If you have any suggestions to make it even better, feel free to share! 😊

Really awesome

Super easy to use and free!!
star lollystar lolly

Response from developer

Thank you so much for your 5-star rating! 🌟 Your support is a great motivation for us to continue developing and improving the app. We wish you a fantastic experience with HiEdu! 🚀

Reseña de Marcus

Es la aplicación más curada y útil me llamo marcushh el ora aya tata
LolomarcuchhLolomarcuchh

Response from developer

¡Hola Marcus! 😊 Muchas gracias por tu reseña y tus amables palabras. Nos alegra mucho saber que consideras nuestra aplicación útil y bien cuidada. Seguiremos trabajando para ofrecer la mejor experiencia posible. ¡Gracias por tu apoyo! 🙏

Rev

Quite fast and easy to use
Guy_sensei123Guy_sensei123

Response from developer

Amazing! Thank you for the 5-star review! 💖 We are so happy to know that you are satisfied with the app. If you have any suggestions to make it even better, feel free to share! 😊

See 61 more reviews

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FAQ

What does the Scientific Calculator fx-991 app do?

This app functions as a powerful scientific calculator designed to help users solve math and science problems. It offers step-by-step solutions for equations, advanced mathematical functions, interactive graphing, an extensive formula library, and a unit converter.

What are the key features of this calculator app?

Key features include a step-by-step equation solver, advanced scientific functions for algebra and calculus, a graphing mode to visualize functions, a comprehensive formula library for math, physics, and chemistry, and a unit converter. It also boasts an interface inspired by the Casio fx-991.

Is this app free to use?

The app is available for free download and use, but it does contain in-app purchases and advertisements. Users may choose to purchase additional features or remove ads through these in-app options.

Who would benefit from using this app?

This app is ideal for high school and college students studying math, physics, and chemistry, as well as engineers and professionals in STEM fields. Its comprehensive features and step-by-step solutions make complex calculations and learning more accessible.

What kind of math problems can this calculator solve?

The calculator can handle a wide range of math problems, including algebra, fractions, trigonometry, derivatives, and integrals. It provides detailed step-by-step solutions to help users understand the problem-solving process.