diff --git a/Row.c b/Row.c
index 9ea3f0731..3ee87cdbc 100644
--- a/Row.c
+++ b/Row.c
@@ -442,6 +442,10 @@ void Row_printLeftAlignedField(RichString* str, int attr, const char* content, u
 }
 
 int Row_printPercentage(float val, char* buffer, size_t n, uint8_t width, int* attr) {
+   assert(width >= 4 && width < n && "Invalid width in Row_printPercentage()");
+   // truncate in favour of abort in xSnprintf()
+   width = (uint8_t)CLAMP(width, 4, n - 1);
+
    if (isNonnegative(val)) {
       if (val < 0.05F)
          *attr = CRT_colors[PROCESS_SHADOW];