diff --git a/types/mapbox__geo-viewport/index.d.ts b/types/mapbox__geo-viewport/index.d.ts
index 6cfa8638f8..d48321ffb8 100644
--- a/types/mapbox__geo-viewport/index.d.ts
+++ b/types/mapbox__geo-viewport/index.d.ts
@@ -1,4 +1,4 @@
-// Type definitions for @mapbox/geo-viewport 0.3
+// Type definitions for @mapbox/geo-viewport 0.4
 // Project: https://github.com/mapbox/geo-viewport
 // Definitions by: Fabio Berta <https://github.com/fnberta>
 // Definitions: https://github.com/DefinitelyTyped/DefinitelyTyped
@@ -10,6 +10,6 @@ export interface GeoViewport {
 
 export type BoundingBox = [number, number, number, number];
 
-export function viewport(bounds: BoundingBox, dimensions: [number, number], minzoom?: number, maxzoom?: number, tileSize?: number): GeoViewport;
+export function viewport(bounds: BoundingBox, dimensions: [number, number], minzoom?: number, maxzoom?: number, tileSize?: number, allowFloat?: boolean): GeoViewport;
 
 export function bounds(viewport: { lon: number; lat: number } | [number, number], zoom: number, dimensions: [number, number], tileSize?: number): BoundingBox;