diff --git a/src/bin/utils/cmds.rs b/src/bin/utils/cmds.rs
index f3dfc9ae4f..58ce808de0 100644
--- a/src/bin/utils/cmds.rs
+++ b/src/bin/utils/cmds.rs
@@ -98,6 +98,7 @@ pool is encrypted, setting this option has no effect on the prediction."),
                          Arg::new("integrity_journal_size")
                          .long("integrity-journal-size")
                          .num_args(1)
+                         .value_parser(clap::value_parser!(u64))
                          .help("Size of the integrity journal. Default is 128 MiB. Units are bytes.")
                          .next_line_help(true)
                     ),
@@ -141,9 +142,8 @@ impl<'a> UtilCommand<'a> for StratisPredictUsage {
                     .get_many::<u128>("filesystem-size")
                     .map(|szs| szs.map(|n| Bytes(*n)).collect::<Vec<_>>()),
                 sub_m
-                    .get_one::<String>("integrity_journal_size")
-                    .map(|s| s.parse::<u64>().map(Bytes::from))
-                    .transpose()?
+                    .get_one::<u64>("integrity_journal_size")
+                    .map(|n| Bytes::from(*n))
                     .map(|b| {
                         if b % 4096u64 != Bytes(0) {
                             Err(format!("Value {b} is not aligned to 4096"))