A basic calculator that gets out of your way
Add, subtract, multiply and divide instantly in your browser. No install, no account, no clutter — just the numbers you need, plus memory keys for anything longer than a one-line sum.
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Fun & original
Getting more out of a basic calculator
Let the memory keys hold your subtotal
When a calculation has several stages — like adding up a receipt before applying tax — press M+ after each subtotal instead of writing numbers down. MR brings the running total back whenever you need it.
Order of operations still applies
A basic calculator works left to right as you press keys, so it won't automatically apply multiplication before addition the way a scientific calculator does. For expressions with mixed operators, calculate the higher-priority part first and carry the result forward.
Typing is faster than clicking
Your keyboard's number row, plus +, -, *, /, Enter and Backspace, all map directly to the buttons above. For a long string of entries, typing is noticeably quicker than reaching for the mouse.
Frequently asked questions
Is DoIt Calculators free to use?
Yes. Every calculator on DoIt Calculators is free, with no account, download or subscription required.
Does the calculator work on mobile phones and tablets?
Yes. The layout adjusts to any screen size, and all buttons are large enough to use comfortably with a thumb.
Can I use my keyboard instead of clicking?
Yes. Number keys, +, -, *, /, Enter (equals) and Backspace (delete last digit) all work directly from your keyboard.
How do the memory buttons work?
M+ adds the current display value to memory, M- subtracts it, MR recalls the stored value, and MC clears memory back to zero.
Does DoIt Calculators store or share my calculations?
No. Every calculation happens locally in your browser. Nothing you type is sent to a server or stored after you close the tab.