# SQRT1_2 Constant

Use SQRT1_2 in Calcul.io. See what this built-in constant represents, enter it in an editable calculation, and review related values and units.

## SQRT1_2

Try it yourself:

```calculio
SQRT1_2
sqrt(1/2)
```

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## SQRT1_2: one over square root of two

**SQRT1_2** is the dimensionless constant 1/√2. It occurs in normalized diagonal directions, 45-degree trigonometry, and equal-amplitude combinations.

## Use

Use it to normalize a two-component vector with equal entries. Compare [SQRT2](https://calcul.io/constants/SQRT2/index.md) and [sqrt](https://calcul.io/function/sqrt/index.md); multiplying the two constants gives one.

## Caveats

It is an exact named constant conceptually, though displayed numerically. Use [norm](https://calcul.io/function/norm/index.md) to verify vector normalization and [pi](https://calcul.io/constants/pi/index.md) for exact angular formulas.

[All constants](https://calcul.io/constants/index.md)