diff --git a/captcha.go b/captcha.go
index 90d2f14..6e813e0 100644
--- a/captcha.go
+++ b/captcha.go
@@ -182,9 +182,9 @@ func drawNoise(img *image.NRGBA, opts *Options) {
 }
 
 func randomColor() color.RGBA {
-	red := rng.Intn(255)
-	green := rng.Intn(255)
-	blue := rng.Intn(255)
+	red := rng.Intn(256)
+	green := rng.Intn(256)
+	blue := rng.Intn(256)
 
 	return color.RGBA{R: uint8(red), G: uint8(green), B: uint8(blue), A: uint8(255)}
 }