diff --git a/src/llhttp/constants.ts b/src/llhttp/constants.ts
index 033ff041..31c16389 100644
--- a/src/llhttp/constants.ts
+++ b/src/llhttp/constants.ts
@@ -211,6 +211,11 @@ export enum STATUSES {
   SWITCHING_PROTOCOLS = 101,
   PROCESSING = 102,
   EARLY_HINTS = 103,
+  RESPONSE_IS_STALE = 110, // Unofficial
+  REVALIDATION_FAILED = 111, // Unofficial
+  DISCONNECTED_OPERATION = 112, // Unofficial
+  HEURISTIC_EXPIRATION = 113, // Unofficial
+  MISCELLANEOUS_WARNING = 199, // Unofficial
   OK = 200,
   CREATED = 201,
   ACCEPTED = 202,
@@ -220,13 +225,16 @@ export enum STATUSES {
   PARTIAL_CONTENT = 206,
   MULTI_STATUS = 207,
   ALREADY_REPORTED = 208,
+  TRANSFORMATION_APPLIED = 214, // Unofficial
   IM_USED = 226,
+  MISCELLANEOUS_PERSISTENT_WARNING = 299, // Unofficial
   MULTIPLE_CHOICES = 300,
   MOVED_PERMANENTLY = 301,
   FOUND = 302,
   SEE_OTHER = 303,
   NOT_MODIFIED = 304,
   USE_PROXY = 305,
+  SWITCH_PROXY = 306, // No longer used
   TEMPORARY_REDIRECT = 307,
   PERMANENT_REDIRECT = 308,
   BAD_REQUEST = 400,
@@ -248,6 +256,8 @@ export enum STATUSES {
   RANGE_NOT_SATISFIABLE = 416,
   EXPECTATION_FAILED = 417,
   IM_A_TEAPOT = 418,
+  PAGE_EXPIRED = 419, // Unofficial
+  ENHANCE_YOUR_CALM = 420, // Unofficial
   MISDIRECTED_REQUEST = 421,
   UNPROCESSABLE_ENTITY = 422,
   LOCKED = 423,
@@ -256,8 +266,21 @@ export enum STATUSES {
   UPGRADE_REQUIRED = 426,
   PRECONDITION_REQUIRED = 428,
   TOO_MANY_REQUESTS = 429,
+  REQUEST_HEADER_FIELDS_TOO_LARGE_UNOFFICIAL = 430, // Unofficial
   REQUEST_HEADER_FIELDS_TOO_LARGE = 431,
+  LOGIN_TIMEOUT = 440, // Unofficial
+  NO_RESPONSE = 444, // Unofficial
+  RETRY_WITH = 449, // Unofficial
+  BLOCKED_BY_PARENTAL_CONTROL = 450, // Unofficial
   UNAVAILABLE_FOR_LEGAL_REASONS = 451,
+  CLIENT_CLOSED_LOAD_BALANCED_REQUEST = 460, // Unofficial
+  INVALID_X_FORWARDED_FOR = 463, // Unofficial
+  REQUEST_HEADER_TOO_LARGE = 494, // Unofficial
+  SSL_CERTIFICATE_ERROR = 495, // Unofficial
+  SSL_CERTIFICATE_REQUIRED = 496, // Unofficial
+  HTTP_REQUEST_SENT_TO_HTTPS_PORT = 497, // Unofficial
+  INVALID_TOKEN = 498, // Unofficial
+  CLIENT_CLOSED_REQUEST = 499, // Unofficial
   INTERNAL_SERVER_ERROR = 500,
   NOT_IMPLEMENTED = 501,
   BAD_GATEWAY = 502,
@@ -270,6 +293,19 @@ export enum STATUSES {
   BANDWIDTH_LIMIT_EXCEEDED = 509,
   NOT_EXTENDED = 510,
   NETWORK_AUTHENTICATION_REQUIRED = 511,
+  WEB_SERVER_UNKNOWN_ERROR = 520, // Unofficial
+  WEB_SERVER_IS_DOWN = 521, // Unofficial
+  CONNECTION_TIMEOUT = 522, // Unofficial
+  ORIGIN_IS_UNREACHABLE = 523, // Unofficial
+  TIMEOUT_OCCURED = 524, // Unofficial
+  SSL_HANDSHAKE_FAILED = 525, // Unofficial
+  INVALID_SSL_CERTIFICATE = 526, // Unofficial
+  RAILGUN_ERROR = 527, // Unofficial
+  SITE_IS_OVERLOADED = 529, // Unofficial
+  SITE_IS_FROZEN = 530, // Unofficial
+  IDENTITY_PROVIDER_AUTHENTICATION_ERROR = 561, // Unofficial
+  NETWORK_READ_TIMEOUT = 598, // Unofficial
+  NETWORK_CONNECT_TIMEOUT = 599, // Unofficial
 }
 
 export const STATUSES_HTTP = [
@@ -277,6 +313,11 @@ export const STATUSES_HTTP = [
   STATUSES.SWITCHING_PROTOCOLS,
   STATUSES.PROCESSING,
   STATUSES.EARLY_HINTS,
+  STATUSES.RESPONSE_IS_STALE,
+  STATUSES.REVALIDATION_FAILED,
+  STATUSES.DISCONNECTED_OPERATION,
+  STATUSES.HEURISTIC_EXPIRATION,
+  STATUSES.MISCELLANEOUS_WARNING,
   STATUSES.OK,
   STATUSES.CREATED,
   STATUSES.ACCEPTED,
@@ -286,13 +327,16 @@ export const STATUSES_HTTP = [
   STATUSES.PARTIAL_CONTENT,
   STATUSES.MULTI_STATUS,
   STATUSES.ALREADY_REPORTED,
+  STATUSES.TRANSFORMATION_APPLIED,
   STATUSES.IM_USED,
+  STATUSES.MISCELLANEOUS_PERSISTENT_WARNING,
   STATUSES.MULTIPLE_CHOICES,
   STATUSES.MOVED_PERMANENTLY,
   STATUSES.FOUND,
   STATUSES.SEE_OTHER,
   STATUSES.NOT_MODIFIED,
   STATUSES.USE_PROXY,
+  STATUSES.SWITCH_PROXY,
   STATUSES.TEMPORARY_REDIRECT,
   STATUSES.PERMANENT_REDIRECT,
   STATUSES.BAD_REQUEST,
@@ -314,6 +358,8 @@ export const STATUSES_HTTP = [
   STATUSES.RANGE_NOT_SATISFIABLE,
   STATUSES.EXPECTATION_FAILED,
   STATUSES.IM_A_TEAPOT,
+  STATUSES.PAGE_EXPIRED,
+  STATUSES.ENHANCE_YOUR_CALM,
   STATUSES.MISDIRECTED_REQUEST,
   STATUSES.UNPROCESSABLE_ENTITY,
   STATUSES.LOCKED,
@@ -322,8 +368,21 @@ export const STATUSES_HTTP = [
   STATUSES.UPGRADE_REQUIRED,
   STATUSES.PRECONDITION_REQUIRED,
   STATUSES.TOO_MANY_REQUESTS,
+  STATUSES.REQUEST_HEADER_FIELDS_TOO_LARGE_UNOFFICIAL,
   STATUSES.REQUEST_HEADER_FIELDS_TOO_LARGE,
+  STATUSES.LOGIN_TIMEOUT,
+  STATUSES.NO_RESPONSE,
+  STATUSES.RETRY_WITH,
+  STATUSES.BLOCKED_BY_PARENTAL_CONTROL,
   STATUSES.UNAVAILABLE_FOR_LEGAL_REASONS,
+  STATUSES.CLIENT_CLOSED_LOAD_BALANCED_REQUEST,
+  STATUSES.INVALID_X_FORWARDED_FOR,
+  STATUSES.REQUEST_HEADER_TOO_LARGE,
+  STATUSES.SSL_CERTIFICATE_ERROR,
+  STATUSES.SSL_CERTIFICATE_REQUIRED,
+  STATUSES.HTTP_REQUEST_SENT_TO_HTTPS_PORT,
+  STATUSES.INVALID_TOKEN,
+  STATUSES.CLIENT_CLOSED_REQUEST,
   STATUSES.INTERNAL_SERVER_ERROR,
   STATUSES.NOT_IMPLEMENTED,
   STATUSES.BAD_GATEWAY,
@@ -336,6 +395,19 @@ export const STATUSES_HTTP = [
   STATUSES.BANDWIDTH_LIMIT_EXCEEDED,
   STATUSES.NOT_EXTENDED,
   STATUSES.NETWORK_AUTHENTICATION_REQUIRED,
+  STATUSES.WEB_SERVER_UNKNOWN_ERROR,
+  STATUSES.WEB_SERVER_IS_DOWN,
+  STATUSES.CONNECTION_TIMEOUT,
+  STATUSES.ORIGIN_IS_UNREACHABLE,
+  STATUSES.TIMEOUT_OCCURED,
+  STATUSES.SSL_HANDSHAKE_FAILED,
+  STATUSES.INVALID_SSL_CERTIFICATE,
+  STATUSES.RAILGUN_ERROR,
+  STATUSES.SITE_IS_OVERLOADED,
+  STATUSES.SITE_IS_FROZEN,
+  STATUSES.IDENTITY_PROVIDER_AUTHENTICATION_ERROR,
+  STATUSES.NETWORK_READ_TIMEOUT,
+  STATUSES.NETWORK_CONNECT_TIMEOUT,
 ];
 
 export enum FINISH {