diff --git a/CHANGES b/CHANGES
index 5e7dd6f05..283baefd7 100644
--- a/CHANGES
+++ b/CHANGES
@@ -125,6 +125,7 @@ Misc:
  - GB: Allow pausing event loop while CPU is blocked
  - GB: Add support for sleep and shutdown callbacks
  - GB: Redo double speed emulation (closes mgba.io/i/1515)
+ - GB: Support loading CGB-on-AGB boot ROM
  - GB Audio: Add channel 4 batching back (fixes mgba.io/i/1313)
  - GB Core: Return the current number of banks for ROM/SRAM, not theoretical max
  - GB I/O: Implement preliminary support for PCM12/PCM34 (closes mgba.io/i/1468)
diff --git a/src/gb/gb.c b/src/gb/gb.c
index 404c660c3..c5b21b548 100644
--- a/src/gb/gb.c
+++ b/src/gb/gb.c
@@ -26,12 +26,13 @@ const uint32_t GB_COMPONENT_MAGIC = 0x400000;
 
 static const uint8_t _knownHeader[4] = { 0xCE, 0xED, 0x66, 0x66};
 
-#define DMG_BIOS_CHECKSUM 0xC2F5CC97
-#define DMG_2_BIOS_CHECKSUM 0x59C8598E
+#define DMG0_BIOS_CHECKSUM 0xC2F5CC97
+#define DMG_BIOS_CHECKSUM 0x59C8598E
 #define MGB_BIOS_CHECKSUM 0xE6920754
 #define SGB_BIOS_CHECKSUM 0xEC8A83B9
 #define SGB2_BIOS_CHECKSUM 0X53D0DD63
 #define CGB_BIOS_CHECKSUM 0x41884E46
+#define AGB_BIOS_CHECKSUM 0xFFD6B0F1
 
 mLOG_DEFINE_CATEGORY(GB, "GB", "gb");
 
@@ -414,11 +415,12 @@ static uint32_t _GBBiosCRC32(struct VFile* vf) {
 bool GBIsBIOS(struct VFile* vf) {
 	switch (_GBBiosCRC32(vf)) {
 	case DMG_BIOS_CHECKSUM:
-	case DMG_2_BIOS_CHECKSUM:
+	case DMG0_BIOS_CHECKSUM:
 	case MGB_BIOS_CHECKSUM:
 	case SGB_BIOS_CHECKSUM:
 	case SGB2_BIOS_CHECKSUM:
 	case CGB_BIOS_CHECKSUM:
+	case AGB_BIOS_CHECKSUM:
 		return true;
 	default:
 		return false;
@@ -623,7 +625,7 @@ void GBDetectModel(struct GB* gb) {
 	if (gb->biosVf) {
 		switch (_GBBiosCRC32(gb->biosVf)) {
 		case DMG_BIOS_CHECKSUM:
-		case DMG_2_BIOS_CHECKSUM:
+		case DMG0_BIOS_CHECKSUM:
 			gb->model = GB_MODEL_DMG;
 			break;
 		case MGB_BIOS_CHECKSUM:
@@ -638,6 +640,9 @@ void GBDetectModel(struct GB* gb) {
 		case CGB_BIOS_CHECKSUM:
 			gb->model = GB_MODEL_CGB;
 			break;
+		case AGB_BIOS_CHECKSUM:
+			gb->model = GB_MODEL_AGB;
+			break;
 		default:
 			gb->biosVf->close(gb->biosVf);
 			gb->biosVf = NULL;