diff --git a/include/helpers.hpp b/include/helpers.hpp
index 010beb5a5..5186a47df 100644
--- a/include/helpers.hpp
+++ b/include/helpers.hpp
@@ -86,6 +86,9 @@ static inline int clz(unsigned int x) {
 // For lack of <ranges>, this adds some more brevity
 #define RANGE(s) std::begin(s), std::end(s)
 
+// MSVC does not inline `strlen()` or `.length()` of a constant string, so we use `sizeof`
+#define QUOTEDSTRLEN(s) (sizeof(s) - 1)
+
 // For ad-hoc RAII in place of a `defer` statement or cross-platform `__attribute__((cleanup))`
 template<typename T>
 struct Defer {
diff --git a/src/asm/lexer.cpp b/src/asm/lexer.cpp
index 7d9d15b52..dd72443f4 100644
--- a/src/asm/lexer.cpp
+++ b/src/asm/lexer.cpp
@@ -21,6 +21,7 @@
 	#include <unistd.h>
 #endif
 
+#include "helpers.hpp" // QUOTEDSTRLEN
 #include "util.hpp"
 
 #include "asm/fixpoint.hpp"
@@ -2233,7 +2234,7 @@ Capture lexer_CaptureRept() {
 					endCapture(capture);
 					// The final ENDR has been captured, but we don't want it!
 					// We know we have read exactly "ENDR", not e.g. an EQUS
-					capture.span.size -= strlen("ENDR");
+					capture.span.size -= QUOTEDSTRLEN("ENDR");
 					return capture;
 				}
 				depth--;
@@ -2279,7 +2280,7 @@ Capture lexer_CaptureMacro() {
 				endCapture(capture);
 				// The ENDM has been captured, but we don't want it!
 				// We know we have read exactly "ENDM", not e.g. an EQUS
-				capture.span.size -= strlen("ENDM");
+				capture.span.size -= QUOTEDSTRLEN("ENDM");
 				return capture;
 
 			default:
diff --git a/src/asm/main.cpp b/src/asm/main.cpp
index b8d988b3e..136b90f1b 100644
--- a/src/asm/main.cpp
+++ b/src/asm/main.cpp
@@ -10,7 +10,7 @@
 
 #include "error.hpp"
 #include "extern/getopt.hpp"
-#include "helpers.hpp" // Defer
+#include "helpers.hpp"
 #include "parser.hpp"
 #include "version.hpp"
 
@@ -45,7 +45,7 @@ static std::string make_escape(std::string &str) {
 			break;
 		escaped.append(str, pos, nextPos - pos);
 		escaped.append("$$");
-		pos = nextPos + sizeof("$") - 1;
+		pos = nextPos + QUOTEDSTRLEN("$");
 	}
 	escaped.append(str, pos, str.length() - pos);
 	return escaped;
diff --git a/src/asm/warning.cpp b/src/asm/warning.cpp
index 63a46b5fa..1707d69be 100644
--- a/src/asm/warning.cpp
+++ b/src/asm/warning.cpp
@@ -10,6 +10,7 @@
 #include <string.h>
 
 #include "error.hpp"
+#include "helpers.hpp" // QUOTEDSTRLEN
 #include "itertools.hpp"
 
 #include "asm/fstack.hpp"
@@ -230,8 +231,8 @@ void processWarningFlag(char const *flag) {
 	}
 
 	// If it's not a meta warning, specially check against `-Werror`
-	if (!strncmp(flag, "error", strlen("error"))) {
-		char const *errorFlag = flag + strlen("error");
+	if (!strncmp(flag, "error", QUOTEDSTRLEN("error"))) {
+		char const *errorFlag = flag + QUOTEDSTRLEN("error");
 
 		switch (*errorFlag) {
 		case '\0':
@@ -254,9 +255,9 @@ void processWarningFlag(char const *flag) {
 
 	WarningState state = setError ? WARNING_ERROR
 	                     // Not an error, then check if this is a negation
-	                     : strncmp(flag, "no-", strlen("no-")) ? WARNING_ENABLED
-	                                                           : WARNING_DISABLED;
-	char const *rootFlag = state == WARNING_DISABLED ? flag + strlen("no-") : flag;
+	                     : strncmp(flag, "no-", QUOTEDSTRLEN("no-")) ? WARNING_ENABLED
+	                                                                 : WARNING_DISABLED;
+	char const *rootFlag = state == WARNING_DISABLED ? flag + QUOTEDSTRLEN("no-") : flag;
 
 	// Is this a "parametric" warning?
 	if (state != WARNING_DISABLED) { // The `no-` form cannot be parametrized
diff --git a/src/gfx/process.cpp b/src/gfx/process.cpp
index 20d92035c..58d2c7a2b 100644
--- a/src/gfx/process.cpp
+++ b/src/gfx/process.cpp
@@ -632,9 +632,9 @@ static std::tuple<DefaultInitVec<size_t>, std::vector<Palette>>
 		char *ptr = buf;
 		for (uint16_t cgbColor : list) {
 			sprintf(ptr, ", $%04x", cgbColor);
-			ptr += 7;
+			ptr += QUOTEDSTRLEN(", $XXXX");
 		}
-		return &buf[2];
+		return &buf[QUOTEDSTRLEN(", ")];
 	};
 
 	// Iterate through proto-palettes, and try mapping them to the specified palettes