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Scientific Calculator fx-991

Scientific Calculator fx-991

Step-by-step Math Solver

404 ratings
72 reviews
With Ads
📚 Education
Free
In-App PurchasesWith Ads

Price history

Details

  • Released
  • Updated
  • February 28, 2023
  • September 7, 2026

Features

Developer

Dinh Phuc
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❓5 answered
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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

What users say

Summarized from real user reviews of Scientific Calculator fx. Based on 404 reviews and a 4.5/5 average, it highlights the 22 positives and 14 negatives reviewers mention most about this Education app.

Positive things

  • 👍Very helpful for classes
  • 💰Free to use
  • 👍Useful without physical calculator
  • 👍Good for engineering students
  • 👍Handles imaginary numbers
  • 👍Super easy to use
  • 🚀Fast and easy to use
  • 👍Very helpful
  • 👍Exactly like physical calculator
  • 👍Faster than normal calculator
  • 👍Accurate and easy to use
  • 👍Replaced physical calculator
  • 👍Useful for school
  • 👍Good for revision
  • 👍Similar to Casio
  • 👍Convenient interface
  • 👍Aesthetic and good for math
  • 👍User interface is great
  • 👍Genuine with many functions
  • 👍Helpful for exams
  • 👍Precise calculations
  • 👍Complete and easy

Negative things

  • 🐛Latest update inconvenient
  • 🐛Update overrides calculations
  • 🐛Mistake in challenge section
  • 🐛Removed important buttons
  • 🐛Cannot find pi button
  • 🐛Simplified interface
  • 🐛Duplicate log key
  • 🐛Cannot change keyboard layout
  • 🐛No 3-dot menu
  • 🐛Can't upgrade to paid version
  • 🐛App crashes on loading screen
  • 🐛App closes on opening
  • 🐛New layout missing CW
  • 🐛'i' key not working after update
See all reviews

What's New in Scientific Calculator fx

1.9.1

September 7, 2026

∙ Updated the formula interface and added the periodic table of elements. ∙ Added lists of favorite and recently viewed formulas. ∙ Improved calculation history for faster viewing and access to results.

More

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

Best one so far

This has been very helpful for my Electro Technology classes. I don’t own a physical one and this is so useful plus free. There are ads but it’s not that bad they are not in your face. For the most part you can ignore them and they don’t throw it in your face forcing you to pay for it.
babyjesus1243babyjesus1243

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! 😊

Annoying problem

The latest update is neither good nor convenient at all, especially when performing a calculation and displaying the result immediately; it overrides the calculation. The older version is much better. I hope the developer fixes this problem because it's annoying.
ahmedeldosokyahmedeldosoky

Response from developer

We’re sorry for the inconvenience. We have tested this feature but haven’t been able to reproduce the issue yet. Could you please describe the exact steps that cause the calculation to be overwritten, or send us a screenshot/screen recording and your device model? This will help us identify and fix the problem. Thank you!

Great for option engg student if calci not available

Its very good
Prabhjot06Prabhjot06

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! 🎉

굳

굳
은헤옹은헤옹

Response from developer

별 5개 평점을 주셔서 정말 감사합니다! 🌟 여러분의 응원은 저희가 앱을 계속 개발하고 개선하는 데 큰 동기가 됩니다. HiEdu와 함께 즐거운 시간을 보내시길 바랍니다! 🚀

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! 🎉

See 67 more reviews

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User experience

🐞

Reported Bugs

6 issues

App crashes on loading screen

Bug

App closes immediately on opening

Bug

App crashes on iOS 18

Bug

App closes after update

Bug

Cannot upgrade to paid version

Bug

'i' key not working after update

Bug
✨

Requested Features

4 requests

Fix update issue with calculation display

Feature

Fix duplicate log key in Fx-350 layout

Feature

Add CW layout for Casio fx991 cw

Feature

Change ☐² to X² and ☐⁻¹ to X⁻¹

Feature

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.