diff --git a/libfwupdplugin/fu-common-version.c b/libfwupdplugin/fu-common-version.c
index a09172de7..854dae8ac 100644
--- a/libfwupdplugin/fu-common-version.c
+++ b/libfwupdplugin/fu-common-version.c
@@ -514,7 +514,7 @@ fu_common_vercmp (const gchar *version_a, const gchar *version_b)
 	if (version_a == NULL || version_b == NULL)
 		return G_MAXINT;
 
-	/* optimisation */
+	/* optimization */
 	if (g_strcmp0 (version_a, version_b) == 0)
 		return 0;
 
diff --git a/libfwupdplugin/fu-udev-device.c b/libfwupdplugin/fu-udev-device.c
index 02e9ac358..2bedd3321 100644
--- a/libfwupdplugin/fu-udev-device.c
+++ b/libfwupdplugin/fu-udev-device.c
@@ -368,7 +368,7 @@ fu_udev_device_probe (FuDevice *device, GError **error)
 			fu_device_set_vendor (device, tmp);
 	}
 
-	/* try harder to find a vendor name the user will recognise */
+	/* try harder to find a vendor name the user will recognize */
 	if (priv->flags & FU_UDEV_DEVICE_FLAG_VENDOR_FROM_PARENT &&
 	    udev_parent != NULL && fu_device_get_vendor (device) == NULL) {
 		g_autoptr(GUdevDevice) device_tmp = g_object_ref (udev_parent);
diff --git a/src/fu-engine.c b/src/fu-engine.c
index f008cf392..0c67ad83d 100644
--- a/src/fu-engine.c
+++ b/src/fu-engine.c
@@ -1380,7 +1380,7 @@ fu_engine_check_requirement_client (FuEngine *self,
 	for (guint i = 0; feature_split[i] != NULL; i++) {
 		FwupdFeatureFlags flag = fwupd_feature_flag_from_string (feature_split[i]);
 
-		/* not recognised */
+		/* not recognized */
 		if (flag == FWUPD_FEATURE_FLAG_LAST) {
 			g_set_error (error,
 				     FWUPD_ERROR,