diff --git a/README.md b/README.md
index cffec4a..3e82557 100644
--- a/README.md
+++ b/README.md
@@ -23,7 +23,7 @@ Check the linked post for another explanation and examples.
 
 To elaborate, you can think of a video as a 3D array of pixels. Say the axes of
 the array are the frame, height, and width, in that order. Then the entry (24,
-500, 900) gives you the pixel in the 499th row and 899th column of the 23rd
+500, 900) gives you the pixel in the 501st row and 901st column of the 25th
 frame of the video (we're 0-indexed). You can imagine "watching" a video as
 just iterating through the frame axis of that array and displaying each 2D
 slice.