diff --git a/core/rexcode/mips/instructions.odin b/core/rexcode/mips/instructions.odin
index 26a4e5357..8ee7cc46e 100644
--- a/core/rexcode/mips/instructions.odin
+++ b/core/rexcode/mips/instructions.odin
@@ -22,7 +22,7 @@ Instruction :: struct #packed {
 	length:        u8,                                 //  1 byte — always 4 for now; will be 2 for future μMIPS / MIPS16e
 	_:             [3]u8,                              //  3 bytes
 }
-#assert(size_of(Instruction) == 72)
+#assert(size_of(Instruction) == 48)
 
 // =============================================================================
 // Builders (mirror x86's `inst_*` shapes; per the cross-arch contract)
diff --git a/core/rexcode/mips/operands.odin b/core/rexcode/mips/operands.odin
index a4619efbe..2fc273b77 100644
--- a/core/rexcode/mips/operands.odin
+++ b/core/rexcode/mips/operands.odin
@@ -64,9 +64,8 @@ Operand :: struct #packed {
 	},
 	kind: Operand_Kind,         // 1 byte
 	size: u8,                   // 1 byte — width hint in bytes (4 = word, 8 = dword, etc.)
-	_:    [6]u8,                // 6 bytes
 }
-#assert(size_of(Operand) == 16)
+#assert(size_of(Operand) == 10)
 
 // -----------------------------------------------------------------------------
 // Generic operand constructors