diff --git a/src/common/system.cpp b/src/common/system.cpp
index 7af792db44c..cf032adfced 100644
--- a/src/common/system.cpp
+++ b/src/common/system.cpp
@@ -11,19 +11,25 @@
 #include <util/string.h>
 #include <util/time.h>
 
-#ifndef WIN32
-#include <sys/stat.h>
-#else
-#include <compat/compat.h>
+#ifdef WIN32
 #include <codecvt>
+#include <compat/compat.h>
+#include <windows.h>
+#else
+#include <sys/stat.h>
+#include <unistd.h>
 #endif
 
 #ifdef HAVE_MALLOPT_ARENA_MAX
 #include <malloc.h>
 #endif
 
+#include <algorithm>
+#include <cstddef>
+#include <cstdint>
 #include <cstdlib>
 #include <locale>
+#include <optional>
 #include <stdexcept>
 #include <string>
 #include <thread>
@@ -105,6 +111,17 @@ int GetNumCores()
     return std::thread::hardware_concurrency();
 }
 
+std::optional<size_t> GetTotalRAM()
+{
+    auto clamp{[](uint64_t v) { return size_t(std::min(v, uint64_t{std::numeric_limits<size_t>::max()})); }};
+#ifdef WIN32
+    if (MEMORYSTATUSEX m{}; (m.dwLength = sizeof(m), GlobalMemoryStatusEx(&m))) return clamp(m.ullTotalPhys);
+#elif defined(__linux__) || defined(__APPLE__)
+    if (long p{sysconf(_SC_PHYS_PAGES)}, s{sysconf(_SC_PAGESIZE)}; p > 0 && s > 0) return clamp(1ULL * p * s);
+#endif
+    return std::nullopt;
+}
+
 // Obtain the application startup time (used for uptime calculation)
 int64_t GetStartupTime()
 {
diff --git a/src/common/system.h b/src/common/system.h
index a4b56be9ac9..2184f1d4c9e 100644
--- a/src/common/system.h
+++ b/src/common/system.h
@@ -9,6 +9,7 @@
 #include <bitcoin-build-config.h> // IWYU pragma: keep
 
 #include <cstdint>
+#include <optional>
 #include <string>
 
 // Application startup time (used for uptime calculation)
@@ -29,4 +30,9 @@ void runCommand(const std::string& strCommand);
  */
 int GetNumCores();
 
+/**
+ * Return the total RAM available on the current system, if detectable.
+ */
+std::optional<size_t> GetTotalRAM();
+
 #endif // BITCOIN_COMMON_SYSTEM_H
diff --git a/src/test/system_tests.cpp b/src/test/system_tests.cpp
index dec4d418290..53db32007ee 100644
--- a/src/test/system_tests.cpp
+++ b/src/test/system_tests.cpp
@@ -8,6 +8,8 @@
 #include <common/run_command.h>
 #include <univalue.h>
 
+#include <common/system.h>
+
 #ifdef ENABLE_EXTERNAL_SIGNER
 #include <util/subprocess.h>
 #endif // ENABLE_EXTERNAL_SIGNER
@@ -16,6 +18,17 @@
 
 BOOST_FIXTURE_TEST_SUITE(system_tests, BasicTestingSetup)
 
+BOOST_AUTO_TEST_CASE(total_ram)
+{
+    BOOST_CHECK_GE(GetTotalRAM(), 1000_MiB);
+
+    if constexpr (SIZE_MAX == UINT64_MAX) {
+        // Upper bound check only on 64-bit: 32-bit systems can reasonably have max memory,
+        // but extremely large values on 64-bit likely indicate detection errors
+        BOOST_CHECK_LT(GetTotalRAM(), 10'000'000_MiB); // >10 TiB memory is unlikely
+    }
+}
+
 #ifdef ENABLE_EXTERNAL_SIGNER
 
 BOOST_AUTO_TEST_CASE(run_command)