Basic calculator

Type a sum or tap the keys. Your answer updates as you go.

On your device · No account

Privacy details

Basic calculator processes your input in this browser. Inputs and results are excluded from analytics. Recent tools save tool names, visit counts and last-visit times. Saved tools store only their names. Draft saving is optional and stays on this device; delete saved text with the draft controls. Loading text from a URL is optional and contacts that server; its URL and your IP address are visible to the server. An optional “Use in” action keeps a handoff in this tab. The next tool removes it on arrival and ignores it if more than a minute has passed.

Copy link includes the inputs you choose to share in the address. Anyone with that link can reopen them. Files and generated results are excluded. Password and key tools share settings only.

Your calculation

Answer

Answer precision

Decimal places

Rounding changes the displayed answer, not the calculation. Copy and download use the displayed precision; memory keeps the calculated value.

Type or paste a sum. Enter calculates; Escape clears.

Memory and recent calculations

Memory: 0

Memory and calculations clear when you leave this page.

Scratch calculator

Check another calculation

Use +, −, ×, ÷, parentheses and %. A percentage is divided by 100. This does not change the main tool.

Reset reloads the tool with its starting values and releases open files and device controls. Saved drafts stay on this device until you delete them.

Links include your inputs and settings. Anyone with the link can see them, so leave out private text. Files and generated results are left out; random draws run again.

Keyboard shortcuts

Updated 2026-09-20

A quick calculation, with room to change your mind

Use this calculator for everyday addition, subtraction, multiplication and division. Parentheses control the order: multiplication and division normally happen before addition and subtraction. Undo restores your previous input; memory lets you carry a value into another sum.

Next: Graph functions online

A worked example

For 200 × 10% + 5, the percent sign turns 10 into 0.1. Multiplying gives 20; adding 5 gives 25. Enter (200 + 5) × 10% instead and the answer is 20.5.

Next: Scientific calculator

Before you use the result

The percent key divides the preceding value by 100; it does not automatically add a percentage to a subtotal. Answers are rounded to 12 significant digits. Browser number arithmetic can round decimals, and very large results are rejected. This tool is for everyday sums, not exact financial accounting or scientific and graphing calculations.

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ToolOctopus. “Basic calculator.” Updated 2026-09-20. https://tooloctopus.com/basic-calculator.

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