diff --git a/drivers/gles2/rasterizer_storage_gles2.cpp b/drivers/gles2/rasterizer_storage_gles2.cpp
index 28c0a65690a9..1a6efc83e207 100644
--- a/drivers/gles2/rasterizer_storage_gles2.cpp
+++ b/drivers/gles2/rasterizer_storage_gles2.cpp
@@ -2309,7 +2309,7 @@ void RasterizerStorageGLES2::mesh_add_surface(RID p_mesh, uint32_t p_format, VS:
 					// UNLESS tangent exists and is also compressed
 					// then it will be oct16 encoded along with tangent
 					attribs[i].normalized = GL_TRUE;
-					attribs[i].size = 4;
+					attribs[i].size = 2;
 					attribs[i].type = GL_SHORT;
 					attributes_stride += 4;
 				} else {
@@ -2330,6 +2330,7 @@ void RasterizerStorageGLES2::mesh_add_surface(RID p_mesh, uint32_t p_format, VS:
 			case VS::ARRAY_TANGENT: {
 				if (p_format & VS::ARRAY_FLAG_USE_OCTAHEDRAL_COMPRESSION) {
 					attribs[i].enabled = false;
+					attribs[VS::ARRAY_NORMAL].size = 4;
 					if (p_format & VS::ARRAY_COMPRESS_TANGENT && p_format & VS::ARRAY_COMPRESS_NORMAL) {
 						// normal and tangent will each be oct16 (2 bytes each)
 						// pack into single vec4<GL_BYTE> for memory bandwidth
diff --git a/drivers/gles3/rasterizer_storage_gles3.cpp b/drivers/gles3/rasterizer_storage_gles3.cpp
index c063e488b7a5..76ae9f9fbadc 100644
--- a/drivers/gles3/rasterizer_storage_gles3.cpp
+++ b/drivers/gles3/rasterizer_storage_gles3.cpp
@@ -3404,7 +3404,7 @@ void RasterizerStorageGLES3::mesh_add_surface(RID p_mesh, uint32_t p_format, VS:
 					// UNLESS tangent exists and is also compressed
 					// then it will be oct16 encoded along with tangent
 					attribs[i].normalized = GL_TRUE;
-					attribs[i].size = 4;
+					attribs[i].size = 2;
 					attribs[i].type = GL_SHORT;
 					attributes_stride += 4;
 				} else {
@@ -3425,6 +3425,7 @@ void RasterizerStorageGLES3::mesh_add_surface(RID p_mesh, uint32_t p_format, VS:
 			case VS::ARRAY_TANGENT: {
 				if (p_format & VS::ARRAY_FLAG_USE_OCTAHEDRAL_COMPRESSION) {
 					attribs[i].enabled = false;
+					attribs[VS::ARRAY_NORMAL].size = 4;
 					if (p_format & VS::ARRAY_COMPRESS_TANGENT && p_format & VS::ARRAY_COMPRESS_NORMAL) {
 						// normal and tangent will each be oct16 (2 bytes each)
 						// pack into single vec4<GL_BYTE> for memory bandwidth