diff --git a/src/CustomMatrixModal.svelte b/src/CustomMatrixModal.svelte
index e1b3bad7..056322d9 100644
--- a/src/CustomMatrixModal.svelte
+++ b/src/CustomMatrixModal.svelte
@@ -44,6 +44,7 @@
   <div class="number-input">
     <NumberInput
       min={1}
+      max={MAX_MATRIX_COLS}
       bind:value={numRows}
       label="Matrix Rows"
     />