diff --git a/src/libsystemd/meson.build b/src/libsystemd/meson.build
index fa28aa09fb..e5c8275fb0 100644
--- a/src/libsystemd/meson.build
+++ b/src/libsystemd/meson.build
@@ -291,6 +291,10 @@ libsystemd_tests += [
                 'sources' : files('sd-journal/test-journal-append.c'),
                 'type' : 'manual',
         },
+        {
+                'sources' : files('sd-journal/test-journal-dump.c'),
+                'type' : 'manual',
+        },
         {
                 'sources' : files('sd-journal/test-journal-verify.c'),
                 'timeout' : 90,
diff --git a/src/libsystemd/sd-journal/journal-file.c b/src/libsystemd/sd-journal/journal-file.c
index 7e941edb19..290b8af73e 100644
--- a/src/libsystemd/sd-journal/journal-file.c
+++ b/src/libsystemd/sd-journal/journal-file.c
@@ -42,11 +42,11 @@
 #include "user-util.h"
 #include "xattr-util.h"
 
-#define DEFAULT_DATA_HASH_TABLE_SIZE (2047ULL*sizeof(HashItem))
-#define DEFAULT_FIELD_HASH_TABLE_SIZE (333ULL*sizeof(HashItem))
+#define DEFAULT_DATA_HASH_TABLE_SIZE 2047U
+#define DEFAULT_FIELD_HASH_TABLE_SIZE 1023U
 
-#define DEFAULT_COMPRESS_THRESHOLD (512ULL)
-#define MIN_COMPRESS_THRESHOLD (8ULL)
+#define DEFAULT_COMPRESS_THRESHOLD 512U
+#define MIN_COMPRESS_THRESHOLD 8U
 
 /* This is the minimum journal file size */
 #define JOURNAL_FILE_SIZE_MIN (512 * U64_KB)             /* 512 KiB */
@@ -1281,15 +1281,14 @@ static int journal_file_setup_data_hash_table(JournalFile *f) {
            beyond 75% fill level. Calculate the hash table size for
            the maximum file size based on these metrics. */
 
-        s = (f->metrics.max_size * 4 / 768 / 3) * sizeof(HashItem);
-        if (s < DEFAULT_DATA_HASH_TABLE_SIZE)
-                s = DEFAULT_DATA_HASH_TABLE_SIZE;
+        s = MAX(f->metrics.max_size * 4 / 768 / 3,
+                DEFAULT_DATA_HASH_TABLE_SIZE);
 
-        log_debug("Reserving %"PRIu64" entries in data hash table.", s / sizeof(HashItem));
+        log_debug("Reserving %"PRIu64" entries in data hash table.", s);
 
         r = journal_file_append_object(f,
                                        OBJECT_DATA_HASH_TABLE,
-                                       offsetof(Object, hash_table.items) + s,
+                                       offsetof(Object, hash_table.items) + s * sizeof(HashItem),
                                        &o, &p);
         if (r < 0)
                 return r;
@@ -1297,7 +1296,7 @@ static int journal_file_setup_data_hash_table(JournalFile *f) {
         memzero(o->hash_table.items, s);
 
         f->header->data_hash_table_offset = htole64(p + offsetof(Object, hash_table.items));
-        f->header->data_hash_table_size = htole64(s);
+        f->header->data_hash_table_size = htole64(s * sizeof(HashItem));
 
         return 0;
 }
@@ -1314,19 +1313,19 @@ static int journal_file_setup_field_hash_table(JournalFile *f) {
          * number should grow very slowly only */
 
         s = DEFAULT_FIELD_HASH_TABLE_SIZE;
-        log_debug("Reserving %"PRIu64" entries in field hash table.", s / sizeof(HashItem));
+        log_debug("Reserving %"PRIu64" entries in field hash table.", s);
 
         r = journal_file_append_object(f,
                                        OBJECT_FIELD_HASH_TABLE,
-                                       offsetof(Object, hash_table.items) + s,
+                                       offsetof(Object, hash_table.items) + s * sizeof(HashItem),
                                        &o, &p);
         if (r < 0)
                 return r;
 
-        memzero(o->hash_table.items, s);
+        memzero(o->hash_table.items, s * sizeof(HashItem));
 
         f->header->field_hash_table_offset = htole64(p + offsetof(Object, hash_table.items));
-        f->header->field_hash_table_size = htole64(s);
+        f->header->field_hash_table_size = htole64(s * sizeof(HashItem));
 
         return 0;
 }
diff --git a/src/libsystemd/sd-journal/test-journal-dump.c b/src/libsystemd/sd-journal/test-journal-dump.c
new file mode 100644
index 0000000000..bac2fb9a66
--- /dev/null
+++ b/src/libsystemd/sd-journal/test-journal-dump.c
@@ -0,0 +1,46 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "errno-util.h"
+#include "journal-file.h"
+#include "log.h"
+#include "main-func.h"
+#include "pager.h"
+#include "strv.h"
+
+static int run(int argc, char *argv[]) {
+        int r = 0;
+        unsigned n = 0;
+
+        _cleanup_(mmap_cache_unrefp) MMapCache *m = mmap_cache_new();
+        assert_se(m);
+
+        pager_open(/* flags= */ 0);
+
+        STRV_FOREACH(s, strv_skip(argv, 1)) {
+                JournalFile *f = NULL;
+
+                int k = journal_file_open(
+                                /* fd= */ -EBADF,
+                                *s,
+                                O_RDONLY,
+                                /* file_flags= */ 0,
+                                0666,
+                                /* compress_threshold_bytes= */ UINT64_MAX,
+                                /* metrics= */ NULL,
+                                m,
+                                /* template= */ NULL,
+                                &f);
+                if (k < 0)
+                        RET_GATHER(r, log_error_errno(k, "Failed to open %s, continuing: %m", *s));
+
+                if (n++ > 0)
+                        puts("");
+
+                journal_file_print_header(f);
+                journal_file_close(f);
+        }
+
+        return r;
+}
+
+DEFINE_MAIN_FUNCTION(run);