diff --git a/doc/release-notes-31483.md b/doc/release-notes-31483.md
new file mode 100644
index 00000000000000..9076aca3eff4f4
--- /dev/null
+++ b/doc/release-notes-31483.md
@@ -0,0 +1,6 @@
+Updated settings
+------
+
+- On 32-bit systems an error is returned on startup if the user passes a
+  `-dbcache` value exceeding 4GiB.
+
diff --git a/src/bitcoin-chainstate.cpp b/src/bitcoin-chainstate.cpp
index 46ca35ea90ad71..51c482607aa8f4 100644
--- a/src/bitcoin-chainstate.cpp
+++ b/src/bitcoin-chainstate.cpp
@@ -123,7 +123,7 @@ int main(int argc, char* argv[])
     util::SignalInterrupt interrupt;
     ChainstateManager chainman{interrupt, chainman_opts, blockman_opts};
 
-    kernel::CacheSizes cache_sizes{MiBToBytes(DEFAULT_KERNEL_CACHE)};
+    kernel::CacheSizes cache_sizes{DEFAULT_KERNEL_CACHE};
     node::ChainstateLoadOptions options;
     auto [status, error] = node::LoadChainstate(chainman, cache_sizes, options);
     if (status != node::ChainstateLoadStatus::SUCCESS) {
diff --git a/src/init.cpp b/src/init.cpp
index a3edeb55241b8e..300b46a3d23f72 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -489,7 +489,7 @@ void SetupServerArgs(ArgsManager& argsman, bool can_listen_ipc)
     argsman.AddArg("-conf=<file>", strprintf("Specify path to read-only configuration file. Relative paths will be prefixed by datadir location (only useable from command line, not configuration file) (default: %s)", BITCOIN_CONF_FILENAME), ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-datadir=<dir>", "Specify data directory", ArgsManager::ALLOW_ANY | ArgsManager::DISALLOW_NEGATION, OptionsCategory::OPTIONS);
     argsman.AddArg("-dbbatchsize", strprintf("Maximum database write batch size in bytes (default: %u)", nDefaultDbBatchSize), ArgsManager::ALLOW_ANY | ArgsManager::DEBUG_ONLY, OptionsCategory::OPTIONS);
-    argsman.AddArg("-dbcache=<n>", strprintf("Maximum database cache size <n> MiB (minimum %d, default: %d). Make sure you have enough RAM. In addition, unused memory allocated to the mempool is shared with this cache (see -maxmempool).", MIN_DB_CACHE, DEFAULT_DB_CACHE), ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
+    argsman.AddArg("-dbcache=<n>", strprintf("Maximum database cache size <n> MiB (minimum %d, default: %d). Make sure you have enough RAM. In addition, unused memory allocated to the mempool is shared with this cache (see -maxmempool).", MIN_DB_CACHE >> 20, DEFAULT_DB_CACHE >> 20), ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-includeconf=<file>", "Specify additional configuration file, relative to the -datadir path (only useable from configuration file, not command line)", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-allowignoredconf", strprintf("For backwards compatibility, treat an unused %s file in the datadir as a warning, not an error.", BITCOIN_CONF_FILENAME), ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-loadblock=<file>", "Imports blocks from external file on startup", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
@@ -1605,7 +1605,11 @@ bool AppInitMain(NodeContext& node, interfaces::BlockAndHeaderTipInfo* tip_info)
     ReadNotificationArgs(args, kernel_notifications);
 
     // cache size calculations
-    auto [index_cache_sizes, kernel_cache_sizes] = CalculateCacheSizes(args, g_enabled_filter_types.size());
+    const auto cache_sizes = CalculateCacheSizes(args, g_enabled_filter_types.size());
+    if (!cache_sizes) {
+        return InitError(_("Failed to calculate cache sizes. Try lowering the -dbcache value."));
+    }
+    auto [index_cache_sizes, kernel_cache_sizes] = *cache_sizes;
 
     LogInfo("Cache configuration:");
     LogInfo("* Using %.1f MiB for block index database", kernel_cache_sizes.block_tree_db * (1.0 / 1024 / 1024));
diff --git a/src/kernel/caches.h b/src/kernel/caches.h
index 9ee5a31e0ae207..e2b687906ac28d 100644
--- a/src/kernel/caches.h
+++ b/src/kernel/caches.h
@@ -9,8 +9,8 @@
 
 #include <algorithm>
 
-//! Suggested default amount of cache reserved for the kernel (MiB)
-static constexpr int64_t DEFAULT_KERNEL_CACHE{450};
+//! Suggested default amount of cache reserved for the kernel (bytes)
+static constexpr size_t DEFAULT_KERNEL_CACHE{MiBToBytes(450)};
 //! Max memory allocated to block tree DB specific cache (bytes)
 static constexpr size_t MAX_BLOCK_DB_CACHE{MiBToBytes(2)};
 //! Max memory allocated to coin DB specific cache (bytes)
diff --git a/src/node/caches.cpp b/src/node/caches.cpp
index 21e2654b4e4f7a..52f3f9332091cb 100644
--- a/src/node/caches.cpp
+++ b/src/node/caches.cpp
@@ -7,31 +7,46 @@
 #include <common/args.h>
 #include <index/txindex.h>
 #include <kernel/caches.h>
+#include <logging.h>
+#include <util/byte_conversion.h>
 
 #include <algorithm>
+#include <optional>
+#include <stdexcept>
 #include <string>
 
 // Unlike for the UTXO database, for the txindex scenario the leveldb cache make
 // a meaningful difference: https://github.com/bitcoin/bitcoin/pull/8273#issuecomment-229601991
-//! Max memory allocated to tx index DB specific cache in MiB.
-static constexpr int64_t MAX_TX_INDEX_CACHE{1024};
-//! Max memory allocated to all block filter index caches combined in MiB.
-static constexpr int64_t MAX_FILTER_INDEX_CACHE{1024};
+//! Max memory allocated to tx index DB specific cache in bytes.
+static constexpr size_t MAX_TX_INDEX_CACHE{MiBToBytes(1024)};
+//! Max memory allocated to all block filter index caches combined in bytes.
+static constexpr size_t MAX_FILTER_INDEX_CACHE{MiBToBytes(1024)};
 
 namespace node {
-CacheSizes CalculateCacheSizes(const ArgsManager& args, size_t n_indexes)
+std::optional<CacheSizes> CalculateCacheSizes(const ArgsManager& args, size_t n_indexes)
 {
-    int64_t nTotalCache = (args.GetIntArg("-dbcache", DEFAULT_DB_CACHE) << 20);
-    nTotalCache = std::max(nTotalCache, MIN_DB_CACHE << 20);
-    IndexCacheSizes sizes;
-    sizes.tx_index = std::min(nTotalCache / 8, args.GetBoolArg("-txindex", DEFAULT_TXINDEX) ? MAX_TX_INDEX_CACHE << 20 : 0);
-    nTotalCache -= sizes.tx_index;
-    sizes.filter_index = 0;
+    int64_t db_cache = args.GetIntArg("-dbcache", DEFAULT_DB_CACHE);
+
+    // negative values are permitted, but interpreted as zero.
+    db_cache = std::max(int64_t{0}, db_cache);
+
+    size_t total_cache = 0;
+    try {
+        total_cache = std::max(MiBToBytes(db_cache), MIN_DB_CACHE);
+    } catch (const std::out_of_range&) {
+        LogError("Cannot allocate more than %d MiB in total for db caches.", std::numeric_limits<size_t>::max() >> 20);
+        return std::nullopt;
+    }
+
+    IndexCacheSizes index_sizes;
+    index_sizes.tx_index = std::min(total_cache / 8, args.GetBoolArg("-txindex", DEFAULT_TXINDEX) ? MAX_TX_INDEX_CACHE : 0);
+    total_cache -= index_sizes.tx_index;
+    index_sizes.filter_index = 0;
     if (n_indexes > 0) {
-        int64_t max_cache = std::min(nTotalCache / 8, MAX_FILTER_INDEX_CACHE << 20);
-        sizes.filter_index = max_cache / n_indexes;
-        nTotalCache -= sizes.filter_index * n_indexes;
+        int64_t max_cache = std::min(total_cache / 8, MAX_FILTER_INDEX_CACHE);
+        index_sizes.filter_index = max_cache / n_indexes;
+        total_cache -= index_sizes.filter_index * n_indexes;
     }
-    return {sizes, kernel::CacheSizes{static_cast<size_t>(nTotalCache)}};
+    return {{index_sizes, kernel::CacheSizes{total_cache}}};
 }
 } // namespace node
diff --git a/src/node/caches.h b/src/node/caches.h
index 45a1623e735e95..258266af7c1c1f 100644
--- a/src/node/caches.h
+++ b/src/node/caches.h
@@ -6,27 +6,28 @@
 #define BITCOIN_NODE_CACHES_H
 
 #include <kernel/caches.h>
+#include <util/byte_conversion.h>
 
 #include <cstddef>
-#include <cstdint>
+#include <optional>
 
 class ArgsManager;
 
-//! min. -dbcache (MiB)
-static constexpr int64_t MIN_DB_CACHE{4};
-//! -dbcache default (MiB)
-static constexpr int64_t DEFAULT_DB_CACHE{DEFAULT_KERNEL_CACHE};
+//! min. -dbcache (bytes)
+static constexpr size_t MIN_DB_CACHE{MiBToBytes(4)};
+//! -dbcache default (bytes)
+static constexpr size_t DEFAULT_DB_CACHE{DEFAULT_KERNEL_CACHE};
 
 namespace node {
 struct IndexCacheSizes {
-    int64_t tx_index;
-    int64_t filter_index;
+    size_t tx_index;
+    size_t filter_index;
 };
 struct CacheSizes {
     IndexCacheSizes index;
     kernel::CacheSizes kernel;
 };
-CacheSizes CalculateCacheSizes(const ArgsManager& args, size_t n_indexes = 0);
+std::optional<CacheSizes> CalculateCacheSizes(const ArgsManager& args, size_t n_indexes = 0);
 } // namespace node
 
 #endif // BITCOIN_NODE_CACHES_H
diff --git a/src/node/chainstate.cpp b/src/node/chainstate.cpp
index 660d2c3289c659..3ee557ae62222f 100644
--- a/src/node/chainstate.cpp
+++ b/src/node/chainstate.cpp
@@ -46,7 +46,7 @@ static ChainstateLoadResult CompleteChainstateInitialization(
     try {
         pblocktree = std::make_unique<BlockTreeDB>(DBParams{
             .path = chainman.m_options.datadir / "blocks" / "index",
-            .cache_bytes = static_cast<size_t>(cache_sizes.block_tree_db),
+            .cache_bytes = cache_sizes.block_tree_db,
             .memory_only = options.block_tree_db_in_memory,
             .wipe_data = options.wipe_block_tree_db,
             .options = chainman.m_options.block_tree_db});
diff --git a/src/test/util/setup_common.cpp b/src/test/util/setup_common.cpp
index 5ede59b82a1807..1c7bfa85d5111e 100644
--- a/src/test/util/setup_common.cpp
+++ b/src/test/util/setup_common.cpp
@@ -252,7 +252,7 @@ ChainTestingSetup::ChainTestingSetup(const ChainType chainType, TestOpts opts)
         LOCK(m_node.chainman->GetMutex());
         m_node.chainman->m_blockman.m_block_tree_db = std::make_unique<BlockTreeDB>(DBParams{
             .path = m_args.GetDataDirNet() / "blocks" / "index",
-            .cache_bytes = static_cast<size_t>(m_kernel_cache_sizes.block_tree_db),
+            .cache_bytes = m_kernel_cache_sizes.block_tree_db,
             .memory_only = true,
         });
     };
diff --git a/src/test/util/setup_common.h b/src/test/util/setup_common.h
index 33ad258457353e..7d7c7b7cd43461 100644
--- a/src/test/util/setup_common.h
+++ b/src/test/util/setup_common.h
@@ -104,7 +104,7 @@ struct BasicTestingSetup {
  * initialization behaviour.
  */
 struct ChainTestingSetup : public BasicTestingSetup {
-    kernel::CacheSizes m_kernel_cache_sizes{node::CalculateCacheSizes(m_args).kernel};
+    kernel::CacheSizes m_kernel_cache_sizes{node::CalculateCacheSizes(m_args).value().kernel};
     bool m_coins_db_in_memory{true};
     bool m_block_tree_db_in_memory{true};
     std::function<void()> m_make_chainman{};
diff --git a/src/validation.h b/src/validation.h
index aea7a4621bbd36..f75337604ad52e 100644
--- a/src/validation.h
+++ b/src/validation.h
@@ -1067,11 +1067,11 @@ class ChainstateManager
 
     //! The total number of bytes available for us to use across all in-memory
     //! coins caches. This will be split somehow across chainstates.
-    int64_t m_total_coinstip_cache{0};
+    size_t m_total_coinstip_cache{0};
     //
     //! The total number of bytes available for us to use across all leveldb
     //! coins databases. This will be split somehow across chainstates.
-    int64_t m_total_coinsdb_cache{0};
+    size_t m_total_coinsdb_cache{0};
 
     //! Instantiate a new chainstate.
     //!