How to Use CAT Exam Screen Calculator: Step By Step Guide

Overview: Learn how to use CAT exam screen calculator effectively with this step-by-step guide. Master quick calculations for CAT exam sections like QA, DILR, and VARC.

The Common Admission Test (CAT) is a big step for many students. It can decide your future. Many people worry about the math section. 

The CAT 2025 exam is scheduled on 30th November 2025. One of the biggest puzzles in the CAT exam is how to use the on-screen calculator. Some students do not even realise it is there. Others use it too much. Knowing how and when to use this tool can help you get a better score. 

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This post will give you smart tips to use the calculator effectively in CAT 2025. You can save time and be more accurate, leading to higher percentiles in QA and DILR sections.

What is CAT Exam Screen Calculator?

You must know that every candidate or test taker gets an on-screen calculator while appearing for the online CBT CAT exam.

It becomes important for you to learn how to use CAT exam screen calculator so that you do not get stuck with its operations and functionality and waste your time only to figure out how it works.

Although candidates have access to the CAT exam screen on a calculator, many prefer to do mental calculations or rough work on a sheet of paper. Since candidates have different preferences, on-screen calculators and rough sheets are provided in the CAT exam.

How Does the CAT Exam Screen Calculator Look and Work?

The CAT on-screen calculator is a basic one. It looks like a simple calculator you would use every day.

Basic Functions

It has all the main math operations:

• Addition (+)
• Subtraction (-)
• Multiplication (x)
• Division (÷)
• Percentage (%)
• Reciprocal (1/x)
• Square Root (√)

Click, Click, Click

The main difference from a normal calculator is how you enter numbers. You have to click each digit with your mouse. For example, to enter "999," you click "9" four times. This takes more time than typing. Be aware of this when deciding to use it.

Memory Functions

The calculator also has memory buttons:

• M+ (Memory Plus): Adds the current number to the memory.
• M- (Memory Minus): Subtracts the current number from the memory.
• MR (Memory Recall): Shows the number saved in memory.
• MC (Memory Clear): Clears the memory.

Use these for problems that have many steps. For example, if you need to add several calculated values together.

Read More: CAT Previous Year Papers to Boost Your Score

How to Use CAT Exam Screen Calculator: The 80-20 Rule

You should not rely on the calculator for everything. The best approach is the 80-20 rule.

1. 80% Mental Math and Pen-Paper Skills

Most of your calculations should happen in your head or on paper. This includes:

• Fractions and Ratios: Know common fractions and how to work with ratios.
• Divisibility Rules: Quickly check if a number can be divided by another without a remainder.
• Odd/Even Properties: Understand how odd and even numbers behave in math.
• Unit Digits and Cyclicity: Use the last digit of a number to quickly eliminate options.

Strong mental math saves a lot of time. It makes you faster than clicking on the calculator.

20% Calculator Assistance

Use the calculator for the remaining 20% of problems. These are times when mental math is hard or too slow. This includes:

• Precise Options: When answers are very close (like 92.43 vs. 92.45), the calculator gives exact values.
• Complex Roots or Percentages: When you need a specific, exact value that is hard to estimate mentally.

By following this rule, you use the calculator only when it truly helps. This keeps you from losing time to endless clicking.

Read More: How to calculate Percentage in the CAT exam?

Where to Find Your CAT Exam Screen Calculator?

When you start your CAT exam, the calculator is not obvious to everyone. Look for a small icon on your screen. It is usually near the top, above the time left display. 

This icon opens the calculator when you click it. It is important to know where it is so you do not waste time searching during the exam. Once you know it is there, you can decide when to use it best.

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When Should You Use CAT Exam Screen Calculator?

The on-screen calculator is not for every math problem. It helps in specific situations. Knowing these times will make your test faster and more accurate.

1.Tackle Big Multiplications

Sometimes, you face very long multiplication problems. These take a lot of time to do by hand. For such problems, the calculator is a lifesaver. It quickly gives you the answer. This saves precious minutes during the exam.

2. Final Step Calculations

You might solve a complex problem and reach the very last step. This last step might need a quick, precise calculation. If it is just one final step and not a long chain of calculations, use the calculator. It is faster than doing long division or multiplication when you are almost done.

3. Options Elimination

The calculator can help you rule out wrong answers. If options are close, like comparing "less than" or "greater than" values, a quick check with the calculator gives you a general idea. This helps narrow down your choices faster.

4. Check Percentages and Roots

• Percentages: Quickly find exact percentages of numbers. This is useful when options are very close.
• Non-Perfect Square Roots: For numbers that are not perfect squares (like square root of 87), the calculator gives you the exact value. Do not give up on a problem just because you need this specific root value.

How to Use CAT Exam Screen Calculator: Tips and Strategies

Using the on-screen calculator is a skill. You need to practice it to be good at it.

1. Home Practice: Pen and Paper First

When you study at home, try to solve problems without a calculator first. Use only pen and paper. This strengthens your basic math skills and mental calculation power.

Avoid using your mobile calculator at home for regular practice, as it is too easy to use and does not prepare you for the click-based CAT calculator.

2. Mock Tests: Learn the On-Screen Calculator

Start using the on-screen calculator in your mock tests. This is the only place where you should use it during practice. It helps you get used to its look and feel. You will learn:

• How long it takes to enter numbers.
• How to handle its basic functions.
• When it truly saves you time versus when it slows you down.

Many official CAT mock tests are available on portals like Supergrads where you can practice using this calculator. Check out the OMET & CAT Test Series Link for comprehensive practice materials.

3. Daily 10-Minute Drill

Dedicate just 10 minutes every day to practice using the on-screen calculator. Think of it like a video game. The goal is to become a "pro." This small daily practice will:

• Improve your speed in clicking numbers and operations.
• Help you remember the location of buttons.
• Prevent errors like clicking "percent" when you meant "root."
• Build muscle memory.

4. Verify Your Work

After you solve a problem using mental math or pen and paper, use the calculator to check your answer. This confirms your calculations. This is especially helpful after you finish a mock test. Go back and verify your answers.

5. Use Official CAT Mocks

Use official CAT previous year papers as mock tests. This helps you understand the types of questions where the calculator is actually useful. It gives you a real feel for when to rely on it and when to trust your mental math. You can find many CAT Exam Blogs with insights into previous year papers.

How to Use CAT Exam Screen Calculator: Smart Hacks for Effective Use

Beyond just knowing when to use it, some tricks can make your calculator use more effective.

1, Handle Chain Calculations with BODMAS

Complex problems often involve multiple operations (like addition, then division). This is where the BODMAS rule (Brackets, Orders, Division, Multiplication, Addition, Subtraction) comes in.

• Common Mistake: Entering all numbers and operations at once without thinking about BODMAS. The calculator might do the operations in a different order than you expect.
• Solution: Use the equals (=) sign often. Finish one part of the calculation, press "=", then start the next part. This ensures the calculator follows the correct order.
• Example: If you want to calculate (125 + 240) ÷ 5, first calculate 125 + 240, then press "=", then ÷ 5, then "=".

2. Leverage Memory Functions for Multi-Step Problems

For problems with many steps, the M+ and M- buttons are very useful.

• Example: If you need to calculate interest and then add it to the principal amount. Calculate the interest, press M+ to save it. Then calculate the principal, and press MR to recall the interest and add them up. This avoids writing down intermediate results and re-entering them.

3. Use the Percentage Symbol Directly

The calculator has a direct percentage symbol (%). You can use it to find percentages quickly.

• Example: To add 15% to 200, you can enter "200 + 15 %". This directly gives you 230. This is faster than calculating 15% of 200 separately and then adding it.

4. Stay Alert and Conscious

Even with a calculator, you must be careful.

• Watch for Typos: Double-check the numbers you enter. A single wrong click can lead to a wrong answer.
• Understand What You Are Doing: Do not just punch numbers. Understand the math problem. The calculator is a tool, not a replacement for your brain.
• BODMAS Awareness: Always keep BODMAS in mind. Know when to press "=" to get the correct result.

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How to Use CAT Exam Screen Calculator: Common Mistakes to Avoid

Many students make mistakes when using the on-screen calculator. Avoid these common traps:

1. Over-Reliance on the Calculator

This is the biggest mistake. Thinking, "There's a calculator, so I don't need mental math," is wrong. Remember the 80-20 rule. If you try to use the calculator for every small calculation, you will:

• Waste Time: Clicking for small calculations is slower than doing them mentally.
• Increase Error Risk: More clicks mean more chances for typos.
• Lose Mental Agility: Your mental math skills will weaken.

2. Not Checking Your Entries

Sometimes, the mouse or system at the exam center might not work perfectly. You might click "3," but the system registers "5." Always visually check the numbers on the calculator screen after you click them. Your strong mental math will help you spot these errors. If your answer is way off the expected range (e.g., a two-digit answer instead of a four-digit answer), something went wrong.

3. Over-Verification

Do not keep re-checking the same calculation multiple times with the calculator. If you are confident in your skills, trust your first calculation. Double-checking every step can eat up valuable exam time. Only verify when you are unsure or for critical final answers.

6. Memory Check Errors

If you use the memory functions (M+, M-), always remember to clear the memory when you start a new problem. If you forget to clear the memory (MC), a saved value from a previous problem might accidentally be added or subtracted from your current calculation. This leads to wrong answers.

Conclusion

Learning to use the on-screen calculator smartly is a skill that takes practice. It will not happen overnight. Start practicing now with your mock tests. Dedicate 10 minutes daily to get comfortable with it. Remember, it is a tool to help you, not replace your math skills. Use it wisely, and you can boost your scores in the CAT exam.