diff --git a/qemu-img.c b/qemu-img.c
index b167376..821cbf6 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -1924,8 +1924,8 @@
         if (status == BLK_DATA && !copy_range) {
             ret = convert_co_read(s, sector_num, n, buf);
             if (ret < 0) {
-                error_report("error while reading sector %" PRId64
-                             ": %s", sector_num, strerror(-ret));
+                error_report("error while reading at byte %lld: %s",
+                             sector_num * BDRV_SECTOR_SIZE, strerror(-ret));
                 s->ret = ret;
             }
         } else if (!s->min_sparse && status == BLK_ZERO) {
@@ -1953,8 +1953,8 @@
                 ret = convert_co_write(s, sector_num, n, buf, status);
             }
             if (ret < 0) {
-                error_report("error while writing sector %" PRId64
-                             ": %s", sector_num, strerror(-ret));
+                error_report("error while writing at byte %lld: %s",
+                             sector_num * BDRV_SECTOR_SIZE, strerror(-ret));
                 s->ret = ret;
             }
         }
diff --git a/tests/qemu-iotests/244.out b/tests/qemu-iotests/244.out
index e6f4dc7..56329de 100644
--- a/tests/qemu-iotests/244.out
+++ b/tests/qemu-iotests/244.out
@@ -33,7 +33,7 @@
 Formatting 'TEST_DIR/t.IMGFMT.src', fmt=IMGFMT size=67108864
 wrote 1048576/1048576 bytes at offset 0
 1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
-qemu-img: error while writing sector 0: Operation not supported
+qemu-img: error while writing at byte 0: Operation not supported
 
 Convert uncompressed, then write compressed data manually:
 Images are identical.