Four Function Calculator
A free four function calculator for the four basic operations — addition, subtraction, multiplication and division. It runs in the browser, keeps a running tape of everything you have worked out, and takes keyboard input, so you can use it without touching the mouse.
Tape — your last 40 calculations
How to use this four function calculator
- Type your first number, using the keypad or your keyboard.
- Press an operator:
+,−,×or÷. - Type the second number and press
=or the Enter key. - Keep going — the result stays on screen and becomes the first number of your next calculation.
Every completed calculation is added to the tape on the right, newest first, so you can check a long run of figures without redoing it. AC clears everything, CE clears only the number you are typing, and the backspace key deletes one digit at a time.
. + - * / work as you would expect. Enter or = calculates, Backspace deletes a digit, and Esc clears everything.What is a four function calculator?
A four function calculator does exactly four things: it adds, subtracts, multiplies and divides. That is the whole specification. It has no trigonometry, no logarithms, no memory of algebraic expressions and no graphing. Most models add a square root key, a percent key and a memory register, and they are still called four-function because those extras are conveniences rather than new operations.
The term comes from physical calculators. A basic desk or pocket calculator is a four-function calculator; a scientific calculator adds powers, roots, logs and trig; a graphing calculator adds a screen that plots functions. The four-function model is the cheapest and the simplest, which is exactly why it is the one allowed in the most places.
| Type | Does | Typical use |
|---|---|---|
| Four function | + − × ÷, often √ and % | Everyday arithmetic, money, elementary and middle school |
| Scientific | Adds powers, roots, logs, trigonometry, constants | High school science and math, engineering |
| Graphing | Adds function plotting, tables, programs | Algebra 2, calculus, statistics courses |
| Financial | Adds time value of money, amortization, cash flows | Finance, accounting, real estate |
Using a four function calculator online
A four function calculator online has one clear advantage over a physical one: it is already in your pocket, and it does not need batteries or a search through a drawer. It also has one disadvantage worth knowing about, which is that a browser tab is not allowed in an exam room.
This one is built to be quick rather than clever. There is no sign-up, nothing is sent to a server, and the page is small enough to load on a slow connection. Once it has loaded, the arithmetic happens entirely on your device.
Where the browser genuinely beats the handheld is the tape. A physical four-function calculator shows you one number and forgets the rest. The tape here keeps your last forty results, so if a total looks wrong you can scroll back and find the line where it went wrong instead of starting again.
Four function calculators and exams
Several standardized tests specify a four-function calculator, either as the minimum allowed or as the maximum. The exam board is the only authority on what is permitted in any given year, so check the current policy for your test rather than relying on what was true previously.
The reason boards specify this category is consistency. If every candidate has at most four operations, no one gains an advantage from a device that can solve equations, store notes or graph a function. That is also why a phone or a browser tab is almost never allowed, even running a calculator that is technically simpler than a permitted handheld: the device can do far more than the calculator on it.
Why a basic calculator can give a different answer
Type 2 + 3 × 4 into a simple four-function calculator, pressing the keys in that order, and many models return 20. The mathematically correct answer is 14.
The reason is that a basic calculator evaluates as you go. When you press ×, it has already finished 2 + 3 and is working with 5. A scientific calculator waits until you press equals and then applies the order of operations, so it multiplies before it adds.
Neither machine is broken — they are following different rules. If your calculation mixes operations, either add brackets by working out each part separately, or use the order of operations calculator, which shows each stage of the working in the correct sequence.
Example: the same keystrokes, two answers
Working out 2 + 3 × 4 on each type of machine.
When four functions are not enough
Plenty of everyday arithmetic is technically just multiplication and division, but is fiddly enough to be worth a purpose-built tool. Working out a sale price means subtracting a percentage of a number from itself; splitting a grade means multiplying each score by its weight before dividing. You can do all of it on the keypad above, but you will make fewer mistakes with a calculator that shows the steps.
Every calculator on this site does that. It updates as you type, prints the formula with your numbers substituted in, and expands to show the working line by line, so you can hand in the method as well as the answer.
Frequently asked questions
What are the four functions on a four function calculator?
Addition, subtraction, multiplication and division. Many models also include a square root key, a percent key and a small memory register, but those are treated as conveniences rather than separate functions, so the device is still called a four-function calculator.
Is a four function calculator the same as a basic calculator?
Yes. “Basic calculator”, “simple calculator” and “four function calculator” all describe the same class of device: one that performs the four arithmetic operations and little else. The four-function name is the one exam boards and product listings tend to use, because it states exactly what the device can do.
Does this calculator work offline?
Once the page has finished loading, yes. All the arithmetic runs in your browser rather than on a server, so the calculator keeps working if your connection drops. Reloading the tab while offline will not work unless your browser has cached the page.
Why does 2 + 3 × 4 give 20 instead of 14?
Because a four-function calculator evaluates each operation as you press it, rather than waiting for equals and applying the order of operations. Pressing 2, +, 3, ×, 4, = calculates 2 + 3 first. The mathematically correct answer is 14, and the order of operations calculator shows why.
Can I use my keyboard instead of clicking?
Yes. Number keys and . + - * / all work, Enter or the equals key calculates, Backspace deletes the last digit and Esc clears everything. The keypad and the keyboard drive the same calculator, so you can switch between them mid-calculation.
What is the tape for?
It records your last forty completed calculations, newest at the top. If a running total comes out wrong, you can scroll back and find the line where it went wrong instead of retyping everything. It clears when you reload the page and is never sent anywhere.
Can I use an online calculator in an exam?
Almost never. Exam boards that allow calculators usually allow a specific handheld model or category, and a phone, tablet or laptop browser is treated as a prohibited device regardless of what is running on it. Check the policy for your specific exam and bring a permitted physical calculator.
How is a four function calculator different from a scientific one?
A scientific calculator adds powers, roots, logarithms, trigonometry and, on most models, correct order-of-operations evaluation of a whole expression before you press equals. A four-function calculator handles one operation at a time. For arithmetic on money and everyday quantities the difference rarely matters.
Is anything I type here stored or sent anywhere?
No. The calculator runs entirely in your browser. Nothing you type is transmitted to a server, and the tape exists only in the page you have open — closing or reloading the tab clears it.
Related calculators
Guides that use this calculator
Longer explanations of the method behind it, with worked examples.
Put this calculator on your own site (free)
Copy this into any page. The calculator stays up to date on its own, works on mobile, and carries a small credit link back here.
https://fourfunctioncalculator.com/