Yes, GRE does provide a digital on-screen calculator (8-digit) for use in the test’s quantitative reasoning section. You cannot bring a physical calculator to the exam. The on-screen calculator has five essential arithmetic functions, i.e., addition, subtraction, multiplication, division, and square root.
In case you are taking the paper-delivered GRE test. You will be given a handheld physical calculator with the same essential functions mentioned above.
Most quantitative questions don’t require any complex calculations, so don’t waste any time using the calculator for every little calculation. Instead, only use it for calculations that you know are time-consuming such as long division, square roots, addition, or subtraction of multiple digit numbers.
Your knowledge of mathematics is crucial in determining whether the calculator’s results are reasonable or not. Don’t rely exclusively on the calculator; you should develop a pretty good mathematical intuition.