---
title: "Scientific Calculator Plus 991 - Reviews, Revenue and Downloads in Thailand | Apple App Store"
description: "NCalc — Powerful Scientific Calculator, Graphing, and Converter  NCalc combines a natural-display scientific calculator, advanced maths tools, a full graphing module (as 83/84 calculator), a large for"
---

# Scientific Calculator Plus 991 — Thailand
> NCalc & CalcES Calculator

![Scientific Calculator Plus 991 App Icon](https://is1-ssl.mzstatic.com/image/thumb/Purple211/v4/bf/05/78/bf05788e-79b8-59ea-dfdc-9200bc568907/app_icon_calces_light-0-0-1x_U007emarketing-0-11-0-85-220.png/434x0w.png)

**Developer:** [Tran Duy](https://apptail.io/developer/tran-duy-Flab)
**Category:** Education
**Rating:** 4.8/5 (7,549 ratings)
**Price:** Free
**Bundle ID:** com.duy.CasioFx
**Store:** Apple App Store
**Country:** Thailand
**Version:** 3.5.8 (released 2026-05-05)
**Original Release:** 2019-04-03
**Languages:** English, Albanian, Arabic, Armenian, Azerbaijani, Basque, Belarusian, Bengali, Bosnian, Bulgarian, Catalan, Croatian, Czech, Danish, Dutch, Finnish, French, German, Greek (modern), Hebrew (modern), Hindi, Hungarian, Indonesian, Italian, Japanese, Kannada, Korean, Lao, Latvian, Lithuanian, Macedonian, Malay, Malayalam, Oriya, Persian, Polish, Portuguese, Panjabi, Romanian, Russian, Serbian, Chinese, Slovak, Spanish, Swahili, Swedish, Thai, Turkish, Ukrainian, Vietnamese

**App Store Link:** [Download on Apple App Store](https://apps.apple.com/th/app/app/id1449106995)
**AppTail Page:** [https://apptail.io/app/scientific-calculator-plus-991-FMq/thailand](https://apptail.io/app/scientific-calculator-plus-991-FMq/thailand)

## Scientific Calculator Plus 991 Description
NCalc — Powerful Scientific Calculator, Graphing, and Converter

NCalc combines a natural-display scientific calculator, advanced maths tools, a full graphing module (as 83/84 calculator), a large formula library, and a comprehensive unit and currency converter—designed for students, engineers, and anyone who loves maths.

◉ Main Calculator Features
- Natural display: Enter expressions exactly as in textbooks—fractions, roots, exponents, and more—see results as written on paper.
- Keyboard layout: Matches popular models for familiarity and speed: 115 ES Plus, 991 ES Plus, 300 ES Plus, and 991 EX.
- Symbolic and numeric modes: Perform exact fraction calculations or evaluate numerically when needed.
- Arbitrary‑precision integers: Work with very large integers without losing accuracy.
- Output types: Choose from fraction, mixed fraction, decimal, recurring decimal, degrees/minutes/seconds, and polar coordinates.
- Angle units: Degree, radian, and gradian (grade).
- Decimal formatter: Display numbers in normal, engineering, engineering SI, scientific, or fixed formats.
- Calculation history: Review and reuse past calculations with ease.
- Copy and paste support for fast data entry and sharing.

◉ Algebra, Calculus, and Core Maths
- Algebra calculations: Expansion, factorisation, simplification, and more.
- Calculus calculator: Derivatives, integrals, and limits of expressions.
- Complex number calculations: Arithmetic, polar/rectangular conversion, exponential, logarithms, powers, roots, and full trigonometric functions.

◉ Equations and Inequalities
- Equation solver: Solve general equations, plus dedicated solvers for quadratic, cubic, and quartic equations.
- System of equations solver: Solve systems with 2, 3, or 4 variables.
- Inequality solvers: Quadratic, cubic, and quartic inequalities with interval‑based solutions.

◉ Matrices and Vectors
- Operations: Addition, subtraction, multiplication for matrices and vectors.
- Advanced tools: Determinant, inverse, transpose, rank, eigenvalues, and eigenvectors.

◉ Statistics and Distributions
- Statistical calculation: Descriptive stats and regression calculation (including a regression plotter).
- Distribution calculation: Normal distribution, binomial distribution, Poisson distribution, t‑distribution, chi‑squared distribution, and F‑distribution.

◉ Number Bases and Formats
- Base‑N calculation: Effortlessly switch between binary, octal, decimal, and hexadecimal, with arithmetic in each base.

◉ Tables, Variables, and Custom Functions
- Table Generator: Generate value tables based on any expression and range.
- Calculator variables: Store values and reuse them across calculations.
- User‑defined functions: Create your own functions to streamline repetitive work.

◉ Built‑ins and Help
- Built‑in constants: A rich set of mathematical and physical constants.
- Built‑in documentation: Access helpful guidance anytime via the Help button.

◉ Formulae
- Extensive formulae collection: Maths and Physics formulae, clearly categorised—ideal for secondary school, sixth form/college, and university students.

◉ Unit Converter
- Currency Converter: Up‑to‑date exchange rates for quick conversions.
- 1,000+ unit conversions: Length, mass, time, energy, power, temperature, pressure, data, and more—organised for fast lookup.

◉ Auto-renewing subscription
You may purchase an auto-renewing subscription through an In-App Purchase.
• Auto-renewable subscription
• Your subscription will be charged to your AppStore account at confirmation of purchase and will automatically renew (at the duration selected) unless auto-renew is turned off at least 24 hours before the end of the current period.
• Current subscription may not be cancelled during the active subscription period; however, you can manage your subscription and/or turn off auto-renewal by visiting your AppStore Account Settings after purchase
• Privacy policy and terms of use: 

## Scientific Calculator Plus 991 Screenshots
- [Screenshot 1](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/6c/69/9f/6c699fb3-5ad2-d58b-e390-36076602bc50/0_APP_IPAD_PRO_3GEN_129_0.jpg/2048x2732.png)
- [Screenshot 2](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/9f/b8/18/9fb81897-ad32-6ed0-a085-40ee11961499/1_APP_IPAD_PRO_3GEN_129_1.jpg/2048x2732.png)
- [Screenshot 3](https://is1-ssl.mzstatic.com/image/thumb/PurpleSource211/v4/15/46/67/154667f7-5797-600d-be19-155b9d0149b5/2_APP_IPAD_PRO_3GEN_129_2.jpg/2048x2732.png)

## Scientific Calculator Plus 991 Rating Breakdown in Thailand
- 5 stars: 6,824 (90%)
- 4 stars: 422 (6%)
- 3 stars: 149 (2%)
- 2 stars: 38 (1%)
- 1 stars: 116 (2%)

## Scientific Calculator Plus 991 Reviews in Thailand

### ***** "Very good"
The function provide very user friendly
-- คนไทยหัดภาษาพม่า, 2024-11-11

### ***** "Very good app"
easy to use and accurate
-- Ssa🦍, 2024-09-30

### ***** "Best scientific calculator for Mac and iOS"
I bought the pro version. Worth it as I could use on both iPhone, iPad and Mac with my purchase. Full of functions. Highly recommended.
-- Bamarlay, 2024-09-21

### ***** "Very Good"
I love it, easy to use
-- Jannabinoid, 2024-09-19

### ***** ":)"
:)
-- Mr vvggycctc, 2024-09-15

### ***** "only five stars"
1. easy to use
2. convenient 
3. smart app
-- hs3kpb, 2024-08-06

### ***** "คณิต"
ดีมากใช้ง่ายโคตรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรรร
-- บังโต้, 2024-06-18

### ****- "ดี"
ผลลัพธ์แสดงเป็นจำนวนคละไม่ได้ พัฒนาต่อไป
-- krukanM, 2024-06-03

### ***** "ดี"
ใช้ดีมากเลยครับ ใช้ทุกวันเลย
-- Poominwza007, 2024-04-24

### ***** "."
แอพน่ารักมากค่ะ
-- ก็เด้งไปเลยสิคะ, 2024-02-29

### ***** "ดีมาก"
ดีที่สุด
-- K1ng4rm, 2023-12-01

### ***** "Very Good for this Machine"
Very Good for this Machine
-- VAJIRAVUDH ARIYA, 2023-11-14

### ***** "These buttons work"
The calculator from websites and google usually have buttons that are harder to press and this calculator makes it a lot easier
-- PanSirawit, 2023-10-24

### ***** "Good"
bettter than some apps i used for 10 yrs
-- Pkaouth, 2023-10-23

### ***** "ใช้งานดี"
แอปดีๆแบบนี้ แนะนำเลยครับใช้ง่ายใช้ได้จริง
-- Aoddys, 2023-10-16

### ***** "เหมาะกับนักศึกษาวิศวกรรมมาก"
ครบจบในแอฟเดียวครับ
-- ต้นบางแค, 2023-10-09

### ***** "ใช้ง่ายดีครับ"
ชอบๆ. ดีมากเลยครับ
-- zuechrn, 2023-08-25

### *---- "เคยซื้อพรี่เมียมไปแล้วแต่อยู่ๆหาย"
หายไปต้องซื้อใหม่งี้อ้อควยย
-- 29094666, 2023-07-31

### ***** "cannot run on macOS 13.3.1"
cannot run on macOS 13.3.1

Please fix the bug
-- chainecs, 2023-05-03

### ***** "Useful of calculator"
Easy to use
-- goysun111, 2023-02-23

[View all Scientific Calculator Plus 991 reviews and detailed analytics on AppTail](https://apptail.io/account/signup?utm_campaign=ai-crawl&utm_content=reviews)

## Scientific Calculator Plus 991 In-App Purchases
| Item | Price |
|------|-------|
| Calculator premium | 199.00 ฿ |
| Calculator month subscription | 79.00 ฿ |
| Calculator yearly subscription | 149.00 ฿ |
| Calculator Pro | 149.00 ฿ |

## Scientific Calculator Plus 991 Store Rankings
| Chart | Country | Category | Rank |
|-------|---------|----------|------|
| Top Free | Vietnam | Education | #14 |
| Top Free | Malaysia | Education | #26 |
| Top Free | Thailand | Education | #28 |
| Top Free | Egypt | Education | #34 |
| Top Free | Philippines | Education | #34 |
| Top Free | Saudi Arabia | Education | #42 |
| Top Free | Peru | Education | #50 |
| Top Free | Lebanon | Education | #50 |
| Top Free | Argentina | Education | #55 |
| Top Free | Hungary | Education | #56 |
| Top Free | Nigeria | Education | #57 |
| Top Free | Kuwait | Education | #62 |
| Top Free | Pakistan | Education | #62 |
| Top Free | Singapore | Education | #69 |
| Top Free | Ecuador | Education | #70 |
| Top Free | Israel | Education | #74 |
| Top Free | Czechia | Education | #83 |
| Top Free | Colombia | Education | #102 |
| Top Free | South Africa | Education | #107 |
| Top Free | United Arab Emirates | Education | #114 |
| Top Free | Mexico | Education | #121 |
| Top Free | Chile | Education | #131 |
| Top Free | Algeria | Education | #137 |
| Top Free | United Kingdom | Education | #144 |
| Top Free | Germany | Education | #190 |
| Top Free | Spain | Education | #201 |
| Top Free | Australia | Education | #202 |
| Top Free | Portugal | Education | #263 |
| Top Free | Hong Kong SAR China | Education | #282 |
| Top Free | Poland | Education | #294 |
| Top Free | Vietnam | Overall | #295 |
| Top Free | Indonesia | Education | #394 |
| Top Free | India | Education | #415 |
| Top Free | Switzerland | Education | #424 |

## Scientific Calculator Plus 991 Discovered Keywords
- calculator
- scientific calculator
- calc
- charts and graphs
- advanced - lite
- ncalc scientific calculator
- 115
- classwiz calc app plus
- algebra math solver
- 12calc

## Apps Similar to Scientific Calculator Plus 991
- [Taculator 84 Graphing Calc](https://apptail.io/app/taculator-84-graphing-calc-ktr/thailand)
- [Dicamon - Giải Toán Lý Hóa Anh](https://apptail.io/app/dicamon-giai-toan-ly-hoa-anh-uuw/thailand)
- [Dịch Tiếng Anh TFlat](https://apptail.io/app/dich-tieng-anh-tflat-vcY/thailand)
- [VietJack - Học Online #1](https://apptail.io/app/vietjack-hoc-online-1-cMeb/thailand)
- [Azota Student](https://apptail.io/app/azota-student-fMeb/thailand)
- [SHub Classroom](https://apptail.io/app/shub-classroom-kMeb/thailand)
- [Đếm Ngược Ngày Thi - THPTQG](https://apptail.io/app/dem-nguoc-ngay-thi-thptqg-UQeb/thailand)
- [ClassWiz Calc App Plus](https://apptail.io/app/classwiz-calc-app-plus-lGjk/thailand)
- [Scientific Calculator fx-991](https://apptail.io/app/scientific-calculator-fx-991-aDTk/thailand)
- [Moon.vn - App học online!](https://apptail.io/app/moonvn-app-hoc-online-QAQl/thailand)

## Scientific Calculator Plus 991 Available In
- [Vietnam](https://apptail.io/app/scientific-calculator-plus-991-FMq/vietnam)
- [China](https://apptail.io/app/scientific-calculator-plus-991-FMq/china)
- [United States](https://apptail.io/app/scientific-calculator-plus-991-FMq/united-states)
- [Saudi Arabia](https://apptail.io/app/scientific-calculator-plus-991-FMq/saudi-arabia)
- [Germany](https://apptail.io/app/scientific-calculator-plus-991-FMq/germany)
- [Thailand](https://apptail.io/app/scientific-calculator-plus-991-FMq/thailand)
- [Egypt](https://apptail.io/app/scientific-calculator-plus-991-FMq/egypt)
- [Mexico](https://apptail.io/app/scientific-calculator-plus-991-FMq/mexico)
- [United Kingdom](https://apptail.io/app/scientific-calculator-plus-991-FMq/united-kingdom)
- [Philippines](https://apptail.io/app/scientific-calculator-plus-991-FMq/philippines)
- [Ghana](https://apptail.io/app/scientific-calculator-plus-991-FMq/ghana)
- [Malaysia](https://apptail.io/app/scientific-calculator-plus-991-FMq/malaysia)
- [India](https://apptail.io/app/scientific-calculator-plus-991-FMq/india)
- [South Africa](https://apptail.io/app/scientific-calculator-plus-991-FMq/south-africa)
- [Colombia](https://apptail.io/app/scientific-calculator-plus-991-FMq/colombia)
- [Australia](https://apptail.io/app/scientific-calculator-plus-991-FMq/australia)
- [United Arab Emirates](https://apptail.io/app/scientific-calculator-plus-991-FMq/united-arab-emirates)
- [Spain](https://apptail.io/app/scientific-calculator-plus-991-FMq/spain)
- [Brazil](https://apptail.io/app/scientific-calculator-plus-991-FMq/brazil)
- [Peru](https://apptail.io/app/scientific-calculator-plus-991-FMq/peru)
- [Singapore](https://apptail.io/app/scientific-calculator-plus-991-FMq/singapore)
- [Canada](https://apptail.io/app/scientific-calculator-plus-991-FMq/canada)
- [Pakistan](https://apptail.io/app/scientific-calculator-plus-991-FMq/pakistan)
- [Chile](https://apptail.io/app/scientific-calculator-plus-991-FMq/chile)
- [Nigeria](https://apptail.io/app/scientific-calculator-plus-991-FMq/nigeria)
- [Kuwait](https://apptail.io/app/scientific-calculator-plus-991-FMq/kuwait)
- [Argentina](https://apptail.io/app/scientific-calculator-plus-991-FMq/argentina)
- [Israel](https://apptail.io/app/scientific-calculator-plus-991-FMq/israel)
- [Ecuador](https://apptail.io/app/scientific-calculator-plus-991-FMq/ecuador)
- [Indonesia](https://apptail.io/app/scientific-calculator-plus-991-FMq/indonesia)
- [South Korea](https://apptail.io/app/scientific-calculator-plus-991-FMq/south-korea)
- [Qatar](https://apptail.io/app/scientific-calculator-plus-991-FMq/qatar)
- [France](https://apptail.io/app/scientific-calculator-plus-991-FMq/france)
- [Sri Lanka](https://apptail.io/app/scientific-calculator-plus-991-FMq/sri-lanka)
- [Algeria](https://apptail.io/app/scientific-calculator-plus-991-FMq/algeria)
- [Hong Kong SAR China](https://apptail.io/app/scientific-calculator-plus-991-FMq/hong-kong)
- [Japan](https://apptail.io/app/scientific-calculator-plus-991-FMq/japan)
- [Taiwan](https://apptail.io/app/scientific-calculator-plus-991-FMq/taiwan)
- [Oman](https://apptail.io/app/scientific-calculator-plus-991-FMq/oman)
- [Italy](https://apptail.io/app/scientific-calculator-plus-991-FMq/italy)
- [Bahrain](https://apptail.io/app/scientific-calculator-plus-991-FMq/bahrain)
- [Nepal](https://apptail.io/app/scientific-calculator-plus-991-FMq/nepal)
- [Panama](https://apptail.io/app/scientific-calculator-plus-991-FMq/panama)
- [Paraguay](https://apptail.io/app/scientific-calculator-plus-991-FMq/paraguay)
- [Türkiye](https://apptail.io/app/scientific-calculator-plus-991-FMq/turkey)
- [Jordan](https://apptail.io/app/scientific-calculator-plus-991-FMq/jordan)
- [Hungary](https://apptail.io/app/scientific-calculator-plus-991-FMq/hungary)
- [Uganda](https://apptail.io/app/scientific-calculator-plus-991-FMq/uganda)
- [Dominican Republic](https://apptail.io/app/scientific-calculator-plus-991-FMq/dominican-republic)
- [Tunisia](https://apptail.io/app/scientific-calculator-plus-991-FMq/tunisia)
- [Belgium](https://apptail.io/app/scientific-calculator-plus-991-FMq/belgium)
- [Czechia](https://apptail.io/app/scientific-calculator-plus-991-FMq/czechia)
- [Senegal](https://apptail.io/app/scientific-calculator-plus-991-FMq/senegal)
- [Kenya](https://apptail.io/app/scientific-calculator-plus-991-FMq/kenya)
- [Russia](https://apptail.io/app/scientific-calculator-plus-991-FMq/russia)
- [Poland](https://apptail.io/app/scientific-calculator-plus-991-FMq/poland)
- [Portugal](https://apptail.io/app/scientific-calculator-plus-991-FMq/portugal)
- [Switzerland](https://apptail.io/app/scientific-calculator-plus-991-FMq/switzerland)
- [Austria](https://apptail.io/app/scientific-calculator-plus-991-FMq/austria)
- [Lebanon](https://apptail.io/app/scientific-calculator-plus-991-FMq/lebanon)
- [Cyprus](https://apptail.io/app/scientific-calculator-plus-991-FMq/cyprus)
- [Ireland](https://apptail.io/app/scientific-calculator-plus-991-FMq/ireland)
- [Honduras](https://apptail.io/app/scientific-calculator-plus-991-FMq/honduras)
- [Netherlands](https://apptail.io/app/scientific-calculator-plus-991-FMq/netherlands)
- [New Zealand](https://apptail.io/app/scientific-calculator-plus-991-FMq/new-zealand)
- [Uruguay](https://apptail.io/app/scientific-calculator-plus-991-FMq/uruguay)
- [Norway](https://apptail.io/app/scientific-calculator-plus-991-FMq/norway)
- [Greece](https://apptail.io/app/scientific-calculator-plus-991-FMq/greece)
- [Slovakia](https://apptail.io/app/scientific-calculator-plus-991-FMq/slovakia)
- [Sweden](https://apptail.io/app/scientific-calculator-plus-991-FMq/sweden)
- [Finland](https://apptail.io/app/scientific-calculator-plus-991-FMq/finland)
- [Namibia](https://apptail.io/app/scientific-calculator-plus-991-FMq/namibia)
- [Angola](https://apptail.io/app/scientific-calculator-plus-991-FMq/angola)
- [Ukraine](https://apptail.io/app/scientific-calculator-plus-991-FMq/ukraine)
- [Croatia](https://apptail.io/app/scientific-calculator-plus-991-FMq/croatia)
- [Romania](https://apptail.io/app/scientific-calculator-plus-991-FMq/romania)
- [Bulgaria](https://apptail.io/app/scientific-calculator-plus-991-FMq/bulgaria)
- [Mali](https://apptail.io/app/scientific-calculator-plus-991-FMq/mali)
- [Jamaica](https://apptail.io/app/scientific-calculator-plus-991-FMq/jamaica)
- [Slovenia](https://apptail.io/app/scientific-calculator-plus-991-FMq/slovenia)
- [Luxembourg](https://apptail.io/app/scientific-calculator-plus-991-FMq/luxembourg)
- [Denmark](https://apptail.io/app/scientific-calculator-plus-991-FMq/denmark)
- [Macao SAR China](https://apptail.io/app/scientific-calculator-plus-991-FMq/macau)
- [Uzbekistan](https://apptail.io/app/scientific-calculator-plus-991-FMq/uzbekistan)
- [Malta](https://apptail.io/app/scientific-calculator-plus-991-FMq/malta)
- [Kazakhstan](https://apptail.io/app/scientific-calculator-plus-991-FMq/kazakhstan)
- [Lithuania](https://apptail.io/app/scientific-calculator-plus-991-FMq/lithuania)
- [Armenia](https://apptail.io/app/scientific-calculator-plus-991-FMq/armenia)
- [Azerbaijan](https://apptail.io/app/scientific-calculator-plus-991-FMq/azerbaijan)
- [Belarus](https://apptail.io/app/scientific-calculator-plus-991-FMq/belarus)
- [Mauritius](https://apptail.io/app/scientific-calculator-plus-991-FMq/mauritius)
- [Iceland](https://apptail.io/app/scientific-calculator-plus-991-FMq/iceland)
- [Brunei](https://apptail.io/app/scientific-calculator-plus-991-FMq/brunei)
- [Estonia](https://apptail.io/app/scientific-calculator-plus-991-FMq/estonia)
- [Madagascar](https://apptail.io/app/scientific-calculator-plus-991-FMq/madagascar)
- [Suriname](https://apptail.io/app/scientific-calculator-plus-991-FMq/suriname)
- [Bermuda](https://apptail.io/app/scientific-calculator-plus-991-FMq/bermuda)
- [Belize](https://apptail.io/app/scientific-calculator-plus-991-FMq/belize)
- [North Macedonia](https://apptail.io/app/scientific-calculator-plus-991-FMq/north-macedonia)
- [Latvia](https://apptail.io/app/scientific-calculator-plus-991-FMq/latvia)
- [Cayman Islands](https://apptail.io/app/scientific-calculator-plus-991-FMq/cayman-islands)
- [Grenada](https://apptail.io/app/scientific-calculator-plus-991-FMq/grenada)

---

## About AppTail

[AppTail](https://apptail.io) is a mobile app intelligence platform providing app analytics, ASO (App Store Optimization) tools, keyword tracking, competitor analysis, revenue estimates, and review monitoring for iOS App Store apps. Track your app's performance, discover ranking keywords, monitor competitors, and analyze market trends.

- [Search Apps](https://apptail.io)
- [Top Charts](https://apptail.io/top-iphone-apps)
- [Sign Up for Full Access](https://apptail.io/account/signup?utm_campaign=ai-crawl&utm_content=footer)

*Data provided by [AppTail](https://apptail.io) - Mobile App Intelligence Platform*