diff --git a/src/bench/bench.cpp b/src/bench/bench.cpp
--- a/src/bench/bench.cpp
+++ b/src/bench/bench.cpp
@@ -99,6 +99,10 @@
         std::cerr << "WARNING: Clock precision is worse than microsecond - "
                      "benchmarks may be less accurate!\n";
     }
+#ifdef DEBUG
+    std::cerr << "WARNING: This is a debug build - may result in slower "
+                 "benchmarks.\n";
+#endif
 
     std::regex reFilter(filter);
     std::smatch baseMatch;
diff --git a/src/init.cpp b/src/init.cpp
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -1377,7 +1377,13 @@
 
     fLogIPs = gArgs.GetBoolArg("-logips", DEFAULT_LOGIPS);
 
-    LogPrintf("%s version %s\n", CLIENT_NAME, FormatFullVersion());
+    std::string version_string = FormatFullVersion();
+#ifdef DEBUG
+    version_string += " (debug build)";
+#else
+    version_string += " (release build)";
+#endif
+    LogPrintf("%s version %s\n", CLIENT_NAME, version_string);
 }
 
 namespace { // Variables internal to initialization process only