# Crosshair and grid line width calculations

:::tip

It is recommend that you first read the [Pixel Perfect Rendering](https://tradingview.github.io/lightweight-charts/docs/plugins/pixel-perfect-rendering.md) page.

:::

The following functions can be used to get the calculated width that the library would use for a crosshair or grid line at a specific device pixel ratio.

```typescript
/**
 * Default grid / crosshair line width in Bitmap sizing
 * @param horizontalPixelRatio - horizontal pixel ratio
 * @returns default grid / crosshair line width in Bitmap sizing
 */
export function gridAndCrosshairBitmapWidth(
    horizontalPixelRatio: number
): number {
    return Math.max(1, Math.floor(horizontalPixelRatio));
}

/**
 * Default grid / crosshair line width in Media sizing
 * @param horizontalPixelRatio - horizontal pixel ratio
 * @returns default grid / crosshair line width in Media sizing
 */
export function gridAndCrosshairMediaWidth(
    horizontalPixelRatio: number
): number {
    return (
        gridAndCrosshairBitmapWidth(horizontalPixelRatio) / horizontalPixelRatio
    );
}

```

---

Documentation for Lightweight Charts™ v5.2 (latest released version).

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