Are calculators allowed on the GMAT? It seems like a pretty straightforward question, but the details are a bit more complicated.
The short answer is: yes and no. In fact, the calculator question holds the key for a strong performance on the exam as a whole. This article explains when calculator use is permitted and, more importantly, when using a calculator isn’t the best approach to solving a given problem.
So if you’re used to using a calculator on math tests, don’t worry! We’ve provided a list of some handy mental math techniques and time saving strategies that will enhance your performance on the Quant section and beyond.
Calculators on the GMAT  Explained
 You are not allowed to bring your own calculator to the GMAT exam.
According to the GMAC, no personal items are allowed in the exam room at any certified test center.
However, the proctor will provide a blank canvas with plenty of space to perform any necessary calculations by hand.

You cannot use a calculator on the Quantitative section.
There’s no reason to be intimidated by the restriction on calculators. Although most of us are used to using calculators for arithmetic, the GMAT is not designed to test your ability to perform complex mathematical operations. The Quant section draws from secondarylevel math and basic algebra and geometry to test other skill sets, such as critical thinking, logical reasoning, and problem solving.
In fact, the majority of the Quant questions can and should be answered without any calculations beyond estimation.
For example, data sufficiency problems, which are more geared towards reasoning than math skills, typically only call for basic calculations and estimation. If you do need to do math, keep in mind that the GMAC designers usually keep numbers simple and avoid decimals. If you see large numbers or complex fractions, it’s a good bet that there’s an easier solution path.
For another example of how mental math can save you time, see our explanation of the movie night combinatorics problem.

You can use an onscreen calculator on the Integrated Reasoning section.
Surprisingly or not, a calculator will be provided for the Integrated Reasoning section. This GMAT calculator has the standard basic functions, CE (clear entry) button, C (clear) button, an sqrt function, a % (percentage) button, and a 1/x button that calculates the reciprocal of the entry currently on the screen. There is also a row with the standard memory functions

 MS (memory store) stores the current entry in the calculator’s memory.
 MR (memory recall) displays the last number stored in the calculator’s memory.
 M+ (memory addition) adds the current entry to the value stored in the calculator’s memory. This button is helpful when you need to add a long series of numbers, but don’t have time to retype each one.
 MC (memory clear) erases whatever is in the current memory. Use it before every new calculation set.
Improve your Mental Math and Reduce Calculator Dependence
Survival Tips & Tricks

Do not overuse the IR calculator.
Although the GMAT provides a basic calculator for the Integrated Reasoning section, don’t use it too often. You’ll waste more time than you save. However, you can apply some of the same solution paths used in the Quant section to problems in Integrated Reasoning.

Practice mental math operations regularly.
Mental math operations are easy to learn with some practice, and mastering mental math can provide a significant morale boost leading up to your test date. You can add, multiply, subtract, and divide when you pay bills, check out at the grocery store, calculate a tip, etc. without using a calculator.
Try putting away the calculator and practicing mental math in your daily life to save time and, ultimately, enhance your GMAT score.

Make accurate estimations
Learning to estimate efficiently is the key to saving considerable amounts of time on the GMAT. Convert unwieldy numbers to more manageable figures, like 0 or 5, for the quicker calculations. Then, you can browse the answer choices and select the answer that’s closest to your preliminary estimate.

Don’t use a calculator when prepping for the Quant section.
Preparing without a calculator is a great way to practice mental math operations outside of your daily life. The test setting and Quant context will help accustom you to the environment. You’ll feel more prepared if you know exactly what to expect on test day.

Familiarize yourself with a basic GMAT calculator and practice using its memory functions.
Since the onscreen calculator will be your only technical aid during the Integrated Reasoning section, it’s smart to spend some time getting used to it. When you’re pressed for time, the calculator’s memory function can be a crucial tool for staying on track with a healthy exam pace.

Look to the answer choices to guide your strategy.
Sometimes, you can eliminate a couple of answer choices immediately.
Even when time is in short supply, you can make educated guesses and use your reasoning skills to boost your chance of arriving at the correct answer.

Don’t panic if you see big numbers.
Keep in mind that the people behind the GMAT are aware that they’re designing questions to be answered without calculators. This limits the difficulty of the arithmetic and encourages testtakers to look for the more straightforward approach.
Contributor: Ilia Dobrev
Date: 26th November, 2020