How to Use a Scientific Calculator

8 min read · Updated September 26, 2026 · by the SolveCalcPro editorial team

A scientific calculator does much more than add and subtract. It knows the order of operations, handles brackets, trigonometry, logarithms, powers and roots, and remembers numbers for later. This guide walks through the keys in the order most people need them, using the SolveCalcPro calculator as the example.

Start with the basics: entering a calculation

Type the numbers and operators in the order you would write them, then press =. A scientific calculator follows the order of operations, so 2+3×4 gives 14, not 20. Use the bracket keys ( and ) whenever you want a different order: (2+3)×4 gives 20.

The screen shows your expression on top and a live preview of the answer underneath. Press AC to clear everything and ⌫ to delete one character.

Powers, roots and factorials

Key	What it does	Example
x²	Squares the number	7 x² = 49
xʸ	Any power	2 xʸ 10 = 1,024
√	Square root	√64 = 8
n!	Factorial	5! = 120
%	Divides by 100	200 × 15% = 30

Press Shift first to reach second functions such as cube root (∛) and x³. See exponents and powers explained for the theory.

Trigonometry and the DEG / RAD switch

The sin, cos and tan keys give ratios of a right triangle. Before using them, check the angle mode. In DEG the calculator expects degrees, so sin(30) = 0.5. In RAD it expects radians, so sin(30) is about −0.988 because 30 radians is a very different angle. If a trig answer looks wrong, the mode is the first thing to check. Read degrees vs radians to learn when to use each.

Pressing Shift then sin gives sin⁻¹ (arcsine), which turns a ratio back into an angle: asin(0.5) = 30 in DEG mode.

Logarithms and e

log is the base-10 logarithm: log(1000) = 3. ln is the natural logarithm, with base e ≈ 2.71828: ln(e) = 1. The Shift versions, 10ˣ and eˣ, undo them. For any other base use the logarithm calculator.

Memory and the last answer

Press M+ to add the number on screen to memory and M− to subtract it. MR recalls it and MC clears it. The Ans key inserts your last result, which is useful for chaining steps: after 12 × 12 = 144, typing Ans ÷ 3 gives 48. The history panel keeps earlier results, and clicking one inserts it.

Code Mode: typing whole expressions

Switch on Code Mode and the display becomes a text box. Type an expression using ordinary keyboard characters and press Enter.

You type	Result
`sqrt(144)+2^3`	20
`sin(30)+cos(60)`	1
`5!/(3!*2!)`	10
`ln(e^2)`	2
`2pi*5` (RAD)	31.4159…

Implicit multiplication works, so 2(3+4) is 14 and 3pi is 3π. Functions accept brackets or a bare number, so sin 30 also works. Full list and shortcuts: Code Mode guide.

Common mistakes

Wrong angle mode for trig, as above.
Forgetting brackets around a numerator or denominator: 1/2+3 is 3.5, but 1/(2+3) is 0.2.
Negative numbers and powers: -3^2 is −9. Type (-3)^2 for 9.
Rounding too early. Keep full precision and round only the final answer.

Practice questions

Test yourself, then tap to check. Answers are calculated by the tools linked below.

What is 35% of 240?
Show answer
35% of 240: 84
Find log₂(64).
Show answer
log base 2 of 64: 6
Calculate 7^4.
Show answer
7^4: 2,401

Frequently asked questions

What is the difference between a scientific and a basic calculator?

A scientific calculator adds trigonometry, logarithms, exponents, roots, factorials, brackets with correct order of operations, and memory. A basic one only does arithmetic.

Why does sin(30) not give 0.5 on my calculator?

It is probably in radian mode. Switch to DEG for degrees.

What does Ans mean?

It inserts the previous answer so you can continue a calculation without retyping.

Can I use this calculator in an exam?

Check your exam rules. Many exams only allow specific approved physical calculators.