Online Calculator with History
A fast, free online calculator with memory, a running history tape and full keyboard support.
About the Online Calculator with History
Sometimes you just need a calculator — and the AlarmDaddy Online Calculator is a clean, fast one that works on any device. It does everything a standard desk calculator does and adds the things people actually miss online: a running history tape so you can see and reuse every result, and memory keys for storing a number while you work.
Type with the on-screen buttons or your keyboard — digits, operators, brackets, Enter to equal, Backspace to delete and Escape to clear all work exactly as you'd expect. The calculator respects the correct order of operations (multiplication and division before addition and subtraction) and supports parentheses, so an expression like 2 + 3 × 4 gives the right answer of 14, not 20. Extra keys cover percentages, square root, squaring and sign change, while the memory keys (MC, MR, M+, M−) let you accumulate a total across several calculations.
Every result you press equals on is saved to the history panel, which stays on your device between visits. Tap any past result to drop it straight back into the calculator and keep going. The layout adapts to your screen — a comfortable two-pane view with the history beside the keypad on desktops and tablets, and big, thumb-friendly buttons with a tucked-away history drawer on phones. Everything runs in your browser, so it's instant and completely private.
How to use this calculator
- 1Tap the buttons or use your keyboard to enter a calculation.
- 2Use brackets, %, √ and x² for more complex sums.
- 3Press = (or Enter) to get the result — it is saved to history.
- 4Tap any history entry to reuse that result; use the memory keys to store running totals.
The formula
The calculator parses your full expression and evaluates it using the standard order of operations (BODMAS/PEMDAS): brackets first, then multiplication and division, then addition and subtraction. This is why 2 + 3 × 4 correctly returns 14. Calculations run entirely in your browser using a safe expression evaluator — no code execution, nothing sent to a server.