diff --git a/src/write.rs b/src/write.rs
index acf9ac98..82764af6 100644
--- a/src/write.rs
+++ b/src/write.rs
@@ -287,7 +287,11 @@ impl<'a> arbitrary::Arbitrary<'a> for FileOptions<'a, ExtendedFileOptions> {
         };
         #[cfg(feature = "deflate-zopfli")]
         if options.compression_method == CompressionMethod::Deflated && bool::arbitrary(u)? {
-            options.zopfli_buffer_size = Some(1 << u.int_in_range(9..=30)?);
+            options.zopfli_buffer_size = Some(1 << u.int_in_range(8..=29)? * if bool::arbitrary(u) {
+                2
+            } else {
+                3
+            });
         }
         u.arbitrary_loop(Some(0), Some((u16::MAX / 4) as u32), |u| {
             options