# Free Online Calculator

Evaluate any arithmetic expression instantly in your browser. Supports +, −, ×, ÷, parentheses and functions. No sign-up, runs offline.

## Run it

- **CLI:** `gizza tool calculator "2 + 2 * 3"`
- **Web:** https://gizza.ai/tools/calculator/
- **Agents:** machine-readable descriptor (parameters JSON Schema) at https://gizza.ai/tools/calculator/tool.json

## Inputs

- `expr` — Expression _(field)_

## Output

- Result (number)

## Query parameters

Open the tool pre-filled and auto-run via URL:

- `expr` — Expression

Example: `https://gizza.ai/tools/calculator/?expr=2%20%2B%202%20%2A%203`

---

## About this calculator

This free online calculator evaluates arithmetic expressions instantly, right
in your browser. Nothing is sent to a server — the math runs locally, works
offline, and needs no sign-up.

### Supported operations

- Add, subtract, multiply, divide: `+`, `-`, `*`, `/`
- Parentheses for grouping: `(1 + 2) * 3`
- Powers with `^`: `2^10`
- Functions: `sqrt`, `sin`, `cos`, `tan`, `ln`, `abs`, and more

### Examples

- `2 + 2 * 3` → `8`
- `sqrt(16)` → `4`
- `3.14 * 2^2` → `12.56`

### FAQ

<details>
<summary>Is it really free?</summary>

Yes — and private. Your input never leaves your device.

</details>

<details>
<summary>Does it work offline?</summary>

Yes, once the page has loaded.

</details>

<details>
<summary>What happens if I divide by zero?</summary>

You get an error, not `Infinity`. Any expression whose result is non-finite —
`1/0`, huge overflows, `sqrt(-1)` — is rejected with a clear message instead of
returning a misleading number.

</details>

<details>
<summary>Which functions and constants can I use?</summary>

Beyond `+ - * /`, `^` for powers and parentheses, you can call `sqrt`, `abs`,
`exp`, `ln`, the trig family (`sin`, `cos`, `tan` and their inverses), `floor`,
`ceil`, `round`, `min` and `max`, and use the constants `pi` and `e` — for
example `sin(pi/2)` or `e^2`.

</details>

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