diff --git a/src/canvas-txt/index.ts b/src/canvas-txt/index.ts
index e8f27ff..6d3bb0d 100644
--- a/src/canvas-txt/index.ts
+++ b/src/canvas-txt/index.ts
@@ -32,7 +32,7 @@ const defaultConfig = {
 }
 
 function drawText(
-  ctx: CanvasRenderingContext2D,
+  ctx: CanvasRenderingContext2D | OffscreenCanvasRenderingContext2D,
   myText: string,
   inputConfig: CanvasTextConfig
 ) {
diff --git a/src/canvas-txt/lib/justify.ts b/src/canvas-txt/lib/justify.ts
index e105955..cca6b41 100644
--- a/src/canvas-txt/lib/justify.ts
+++ b/src/canvas-txt/lib/justify.ts
@@ -1,5 +1,5 @@
 export interface JustifyLineProps {
-  ctx: CanvasRenderingContext2D
+  ctx: CanvasRenderingContext2D | OffscreenCanvasRenderingContext2D
   line: string
   spaceWidth: number
   spaceChar: string
diff --git a/src/canvas-txt/lib/split-text.ts b/src/canvas-txt/lib/split-text.ts
index ecfb095..2db268f 100644
--- a/src/canvas-txt/lib/split-text.ts
+++ b/src/canvas-txt/lib/split-text.ts
@@ -4,7 +4,7 @@ import justifyLine from './justify'
 const SPACE = '\u{200a}'
 
 export interface SplitTextProps {
-  ctx: CanvasRenderingContext2D
+  ctx: CanvasRenderingContext2D | OffscreenCanvasRenderingContext2D
   text: string
   justify: boolean
   width: number
diff --git a/src/canvas-txt/lib/text-height.ts b/src/canvas-txt/lib/text-height.ts
index 284ceb8..abcc939 100644
--- a/src/canvas-txt/lib/text-height.ts
+++ b/src/canvas-txt/lib/text-height.ts
@@ -1,5 +1,5 @@
 interface GetTextHeightProps {
-  ctx: CanvasRenderingContext2D
+  ctx: CanvasRenderingContext2D | OffscreenCanvasRenderingContext2D
   text: string
   style: string
 }