Basic Calculator
A clean everyday calculator for quick arithmetic (full keyboard support included).
Need trig, logs, powers or roots? Use the scientific calculator
This is a straightforward calculator for everyday arithmetic: add, subtract, multiply, divide, percentages and memory.
It is the right tool for splitting a bill, checking a receipt or working out change. For trigonometry, powers or logarithms, use the scientific calculator instead.
What a basic calculator does
A basic calculator handles the four everyday operations: add, subtract, multiply and divide, plus a percent key and a memory.
That covers almost all day-to-day arithmetic. Splitting a restaurant bill, checking a receipt, working out change, converting a recipe, adding up hours.
What it deliberately leaves out is trigonometry, logarithms and powers. If you need those, or you are working through an equation where the order of operations matters, use the scientific calculator instead.
What to enter
- AC and CE
- AC clears everything and starts fresh. CE clears only the number you are currently typing, so a mistyped digit does not cost you the whole sum.
- %
- Turns the number into a percentage of what came before. 200 + 10 % gives 220, because it reads the 10 as 10% of 200.
- M+ / MR / MC
- Memory. M+ adds the displayed number to a stored total, MR recalls it, MC clears it. Useful for adding up a column without writing anything down.
- +/−
- Flips the sign of the number on screen, for entering a negative.
What this assumes
Results use standard floating-point arithmetic, so long decimals may show a tiny rounding difference on the final digit.
How to calculate everyday arithmetic
The one thing worth understanding is the percent key, because it behaves differently depending on the operation in front of it.
Finding a percentage of something. For 15% of 80, type 80 × 15 %. That gives 12.
Adding a percentage on. For 20% VAT on 50, type 50 + 20 %. That gives 60, not 70, because the calculator reads 20 as 20% of 50.
Taking a percentage off. For 30% off 90, type 90 − 30 %, giving 63.
See a worked example: splitting a $86.40 bill between 4 people with a 15% tip
- Bill
- $86.40
- Tip
- 15%
- People
- 4
Add the tip: 86.40 + 15 % gives 99.36.
Divide by the group: 99.36 ÷ 4 = 24.84.
So each person pays $24.84.
Worth a sanity check: 15% of 86.40 is about 13, and 86 + 13 is roughly 99. The answer is in the right region.
$24.84 each
Frequently asked questions
A basic one does the four operations and percent. A scientific one adds trigonometry, logarithms, powers, roots and statistics.
The subtler difference matters more: a scientific calculator applies the order of operations, so 2 + 3 × 4 gives 14. Many basic calculators work in the order you press keys and answer 20.
Because the percent key reads the 20 as 20% of the number before it, and 20% of 50 is 10. So it adds 10, giving 60.
If you genuinely wanted to add 20, use the plain number rather than the percent key.
AC wipes everything, including anything part-way through. CE clears only the number currently on screen.
So if you are halfway through 250 × and fumble the second number, press CE and retype it. Press AC and you start the whole sum again.
M+ adds what is on screen to a running stored total, MR brings that total back, and MC clears it.
They are handy for totalling a list where each entry needs working out first: calculate each one, press M+, then MR at the end for the total.
Results are estimates for general information only and are not professional financial, medical, or legal advice. Read our full disclaimer.
Last updated: September 3, 2026