---
id: constants
title: 📋 Constants
description: Core HTTP constants used throughout Fiber.
sidebar_position: 10
---

### HTTP methods (mirrors `net/http`)

```go
const (
    MethodGet     = "GET"     // RFC 7231, 4.3.1
    MethodHead    = "HEAD"    // RFC 7231, 4.3.2
    MethodPost    = "POST"    // RFC 7231, 4.3.3
    MethodPut     = "PUT"     // RFC 7231, 4.3.4
    MethodPatch   = "PATCH"   // RFC 5789
    MethodDelete  = "DELETE"  // RFC 7231, 4.3.5
    MethodConnect = "CONNECT" // RFC 7231, 4.3.6
    MethodOptions = "OPTIONS" // RFC 7231, 4.3.7
    MethodTrace   = "TRACE"   // RFC 7231, 4.3.8
    methodUse     = "USE"
)
```

### Common MIME types

```go
const (
    MIMETextXML                          = "text/xml"
    MIMETextHTML                         = "text/html"
    MIMETextPlain                        = "text/plain"
    MIMETextJavaScript                   = "text/javascript"
    MIMETextCSS                          = "text/css"
    MIMEApplicationXML                   = "application/xml"
    MIMEApplicationJSON                  = "application/json"
    MIMEApplicationCBOR                  = "application/cbor"
    MIMEApplicationForm                  = "application/x-www-form-urlencoded"
    MIMEOctetStream                      = "application/octet-stream"
    MIMEMultipartForm                    = "multipart/form-data"

    MIMETextXMLCharsetUTF8               = "text/xml; charset=utf-8"
    MIMETextHTMLCharsetUTF8              = "text/html; charset=utf-8"
    MIMETextPlainCharsetUTF8             = "text/plain; charset=utf-8"
    MIMETextJavaScriptCharsetUTF8        = "text/javascript; charset=utf-8"
    MIMETextCSSCharsetUTF8               = "text/css; charset=utf-8"
    MIMEApplicationXMLCharsetUTF8        = "application/xml; charset=utf-8"
    MIMEApplicationJSONCharsetUTF8       = "application/json; charset=utf-8"
)
```

### HTTP status codes (mirrors `net/http`)

```go
const (
    StatusContinue                      = 100 // RFC 7231, 6.2.1
    StatusSwitchingProtocols            = 101 // RFC 7231, 6.2.2
    StatusProcessing                    = 102 // RFC 2518, 10.1
    StatusEarlyHints                    = 103 // RFC 8297
    StatusOK                            = 200 // RFC 7231, 6.3.1
    StatusCreated                       = 201 // RFC 7231, 6.3.2
    StatusAccepted                      = 202 // RFC 7231, 6.3.3
    StatusNonAuthoritativeInformation   = 203 // RFC 7231, 6.3.4
    StatusNoContent                     = 204 // RFC 7231, 6.3.5
    StatusResetContent                  = 205 // RFC 7231, 6.3.6
    StatusPartialContent                = 206 // RFC 7233, 4.1
    StatusMultiStatus                   = 207 // RFC 4918, 11.1
    StatusAlreadyReported               = 208 // RFC 5842, 7.1
    StatusIMUsed                        = 226 // RFC 3229, 10.4.1
    StatusMultipleChoices               = 300 // RFC 7231, 6.4.1
    StatusMovedPermanently              = 301 // RFC 7231, 6.4.2
    StatusFound                         = 302 // RFC 7231, 6.4.3
    StatusSeeOther                      = 303 // RFC 7231, 6.4.4
    StatusNotModified                   = 304 // RFC 7232, 4.1
    StatusUseProxy                      = 305 // RFC 7231, 6.4.5
    StatusSwitchProxy                   = 306 // RFC 9110, 15.4.7 (Unused)
    StatusTemporaryRedirect             = 307 // RFC 7231, 6.4.7
    StatusPermanentRedirect             = 308 // RFC 7538, 3
    StatusBadRequest                    = 400 // RFC 7231, 6.5.1
    StatusUnauthorized                  = 401 // RFC 7235, 3.1
    StatusPaymentRequired               = 402 // RFC 7231, 6.5.2
    StatusForbidden                     = 403 // RFC 7231, 6.5.3
    StatusNotFound                      = 404 // RFC 7231, 6.5.4
    StatusMethodNotAllowed              = 405 // RFC 7231, 6.5.5
    StatusNotAcceptable                 = 406 // RFC 7231, 6.5.6
    StatusProxyAuthRequired             = 407 // RFC 7235, 3.2
    StatusRequestTimeout                = 408 // RFC 7231, 6.5.7
    StatusConflict                      = 409 // RFC 7231, 6.5.8
    StatusGone                          = 410 // RFC 7231, 6.5.9
    StatusLengthRequired                = 411 // RFC 7231, 6.5.10
    StatusPreconditionFailed            = 412 // RFC 7232, 4.2
    StatusRequestEntityTooLarge         = 413 // RFC 7231, 6.5.11
    StatusRequestURITooLong             = 414 // RFC 7231, 6.5.12
    StatusUnsupportedMediaType          = 415 // RFC 7231, 6.5.13
    StatusRequestedRangeNotSatisfiable  = 416 // RFC 7233, 4.4
    StatusExpectationFailed             = 417 // RFC 7231, 6.5.14
    StatusTeapot                        = 418 // RFC 7168, 2.3.3
    StatusMisdirectedRequest            = 421 // RFC 7540, 9.1.2
    StatusUnprocessableEntity           = 422 // RFC 4918, 11.2
    StatusLocked                        = 423 // RFC 4918, 11.3
    StatusFailedDependency              = 424 // RFC 4918, 11.4
    StatusTooEarly                      = 425 // RFC 8470, 5.2.
    StatusUpgradeRequired               = 426 // RFC 7231, 6.5.15
    StatusPreconditionRequired          = 428 // RFC 6585, 3
    StatusTooManyRequests               = 429 // RFC 6585, 4
    StatusRequestHeaderFieldsTooLarge   = 431 // RFC 6585, 5
    StatusUnavailableForLegalReasons    = 451 // RFC 7725, 3
    StatusInternalServerError           = 500 // RFC 7231, 6.6.1
    StatusNotImplemented                = 501 // RFC 7231, 6.6.2
    StatusBadGateway                    = 502 // RFC 7231, 6.6.3
    StatusServiceUnavailable            = 503 // RFC 7231, 6.6.4
    StatusGatewayTimeout                = 504 // RFC 7231, 6.6.5
    StatusHTTPVersionNotSupported       = 505 // RFC 7231, 6.6.6
    StatusVariantAlsoNegotiates         = 506 // RFC 2295, 8.1
    StatusInsufficientStorage           = 507 // RFC 4918, 11.5
    StatusLoopDetected                  = 508 // RFC 5842, 7.2
    StatusNotExtended                   = 510 // RFC 2774, 7
    StatusNetworkAuthenticationRequired = 511 // RFC 6585, 6
)
```

### Errors

```go
var (
    ErrBadRequest                    = NewError(StatusBadRequest)                    // RFC 7231, 6.5.1
    ErrUnauthorized                  = NewError(StatusUnauthorized)                  // RFC 7235, 3.1
    ErrPaymentRequired               = NewError(StatusPaymentRequired)               // RFC 7231, 6.5.2
    ErrForbidden                     = NewError(StatusForbidden)                     // RFC 7231, 6.5.3
    ErrNotFound                      = NewError(StatusNotFound)                      // RFC 7231, 6.5.4
    ErrMethodNotAllowed              = NewError(StatusMethodNotAllowed)              // RFC 7231, 6.5.5
    ErrNotAcceptable                 = NewError(StatusNotAcceptable)                 // RFC 7231, 6.5.6
    ErrProxyAuthRequired             = NewError(StatusProxyAuthRequired)             // RFC 7235, 3.2
    ErrRequestTimeout                = NewError(StatusRequestTimeout)                // RFC 7231, 6.5.7
    ErrConflict                      = NewError(StatusConflict)                      // RFC 7231, 6.5.8
    ErrGone                          = NewError(StatusGone)                          // RFC 7231, 6.5.9
    ErrLengthRequired                = NewError(StatusLengthRequired)                // RFC 7231, 6.5.10
    ErrPreconditionFailed            = NewError(StatusPreconditionFailed)            // RFC 7232, 4.2
    ErrRequestEntityTooLarge         = NewError(StatusRequestEntityTooLarge)         // RFC 7231, 6.5.11
    ErrRequestURITooLong             = NewError(StatusRequestURITooLong)             // RFC 7231, 6.5.12
    ErrUnsupportedMediaType          = NewError(StatusUnsupportedMediaType)          // RFC 7231, 6.5.13
    ErrRequestedRangeNotSatisfiable  = NewError(StatusRequestedRangeNotSatisfiable)  // RFC 7233, 4.4
    ErrExpectationFailed             = NewError(StatusExpectationFailed)             // RFC 7231, 6.5.14
    ErrTeapot                        = NewError(StatusTeapot)                        // RFC 7168, 2.3.3
    ErrMisdirectedRequest            = NewError(StatusMisdirectedRequest)            // RFC 7540, 9.1.2
    ErrUnprocessableEntity           = NewError(StatusUnprocessableEntity)           // RFC 4918, 11.2
    ErrLocked                        = NewError(StatusLocked)                        // RFC 4918, 11.3
    ErrFailedDependency              = NewError(StatusFailedDependency)              // RFC 4918, 11.4
    ErrTooEarly                      = NewError(StatusTooEarly)                      // RFC 8470, 5.2.
    ErrUpgradeRequired               = NewError(StatusUpgradeRequired)               // RFC 7231, 6.5.15
    ErrPreconditionRequired          = NewError(StatusPreconditionRequired)          // RFC 6585, 3
    ErrTooManyRequests               = NewError(StatusTooManyRequests)               // RFC 6585, 4
    ErrRequestHeaderFieldsTooLarge   = NewError(StatusRequestHeaderFieldsTooLarge)   // RFC 6585, 5
    ErrUnavailableForLegalReasons    = NewError(StatusUnavailableForLegalReasons)    // RFC 7725, 3
    ErrInternalServerError           = NewError(StatusInternalServerError)           // RFC 7231, 6.6.1
    ErrNotImplemented                = NewError(StatusNotImplemented)                // RFC 7231, 6.6.2
    ErrBadGateway                    = NewError(StatusBadGateway)                    // RFC 7231, 6.6.3
    ErrServiceUnavailable            = NewError(StatusServiceUnavailable)            // RFC 7231, 6.6.4
    ErrGatewayTimeout                = NewError(StatusGatewayTimeout)                // RFC 7231, 6.6.5
    ErrHTTPVersionNotSupported       = NewError(StatusHTTPVersionNotSupported)       // RFC 7231, 6.6.6
    ErrVariantAlsoNegotiates         = NewError(StatusVariantAlsoNegotiates)         // RFC 2295, 8.1
    ErrInsufficientStorage           = NewError(StatusInsufficientStorage)           // RFC 4918, 11.5
    ErrLoopDetected                  = NewError(StatusLoopDetected)                  // RFC 5842, 7.2
    ErrNotExtended                   = NewError(StatusNotExtended)                   // RFC 2774, 7
    ErrNetworkAuthenticationRequired = NewError(StatusNetworkAuthenticationRequired) // RFC 6585, 6
)
```

HTTP Headers were copied from net/http.

```go
const (
    HeaderAuthorization                      = "Authorization"
    HeaderProxyAuthenticate                  = "Proxy-Authenticate"
    HeaderProxyAuthorization                 = "Proxy-Authorization"
    HeaderWWWAuthenticate                    = "WWW-Authenticate"
    HeaderAge                                = "Age"
    HeaderCacheControl                       = "Cache-Control"
    HeaderClearSiteData                      = "Clear-Site-Data"
    HeaderExpires                            = "Expires"
    HeaderPragma                             = "Pragma"
    HeaderWarning                            = "Warning"
    HeaderAcceptCH                           = "Accept-CH"
    HeaderAcceptCHLifetime                   = "Accept-CH-Lifetime"
    HeaderContentDPR                         = "Content-DPR"
    HeaderDPR                                = "DPR"
    HeaderEarlyData                          = "Early-Data"
    HeaderSaveData                           = "Save-Data"
    HeaderViewportWidth                      = "Viewport-Width"
    HeaderWidth                              = "Width"
    HeaderETag                               = "ETag"
    HeaderIfMatch                            = "If-Match"
    HeaderIfModifiedSince                    = "If-Modified-Since"
    HeaderIfNoneMatch                        = "If-None-Match"
    HeaderIfUnmodifiedSince                  = "If-Unmodified-Since"
    HeaderLastModified                       = "Last-Modified"
    HeaderVary                               = "Vary"
    HeaderConnection                         = "Connection"
    HeaderKeepAlive                          = "Keep-Alive"
    HeaderAccept                             = "Accept"
    HeaderAcceptCharset                      = "Accept-Charset"
    HeaderAcceptEncoding                     = "Accept-Encoding"
    HeaderAcceptLanguage                     = "Accept-Language"
    HeaderCookie                             = "Cookie"
    HeaderExpect                             = "Expect"
    HeaderMaxForwards                        = "Max-Forwards"
    HeaderSetCookie                          = "Set-Cookie"
    HeaderAccessControlAllowCredentials      = "Access-Control-Allow-Credentials"
    HeaderAccessControlAllowHeaders          = "Access-Control-Allow-Headers"
    HeaderAccessControlAllowMethods          = "Access-Control-Allow-Methods"
    HeaderAccessControlAllowOrigin           = "Access-Control-Allow-Origin"
    HeaderAccessControlExposeHeaders         = "Access-Control-Expose-Headers"
    HeaderAccessControlMaxAge                = "Access-Control-Max-Age"
    HeaderAccessControlRequestHeaders        = "Access-Control-Request-Headers"
    HeaderAccessControlRequestMethod         = "Access-Control-Request-Method"
    HeaderOrigin                             = "Origin"
    HeaderTimingAllowOrigin                  = "Timing-Allow-Origin"
    HeaderXPermittedCrossDomainPolicies      = "X-Permitted-Cross-Domain-Policies"
    HeaderDNT                                = "DNT"
    HeaderTk                                 = "Tk"
    HeaderContentDisposition                 = "Content-Disposition"
    HeaderContentEncoding                    = "Content-Encoding"
    HeaderContentLanguage                    = "Content-Language"
    HeaderContentLength                      = "Content-Length"
    HeaderContentLocation                    = "Content-Location"
    HeaderContentType                        = "Content-Type"
    HeaderForwarded                          = "Forwarded"
    HeaderVia                                = "Via"
    HeaderXForwardedFor                      = "X-Forwarded-For"
    HeaderXForwardedHost                     = "X-Forwarded-Host"
    HeaderXForwardedProto                    = "X-Forwarded-Proto"
    HeaderXForwardedProtocol                 = "X-Forwarded-Protocol"
    HeaderXForwardedSsl                      = "X-Forwarded-Ssl"
    HeaderXUrlScheme                         = "X-Url-Scheme"
    HeaderLocation                           = "Location"
    HeaderFrom                               = "From"
    HeaderHost                               = "Host"
    HeaderReferer                            = "Referer"
    HeaderReferrerPolicy                     = "Referrer-Policy"
    HeaderUserAgent                          = "User-Agent"
    HeaderAllow                              = "Allow"
    HeaderServer                             = "Server"
    HeaderAcceptRanges                       = "Accept-Ranges"
    HeaderContentRange                       = "Content-Range"
    HeaderIfRange                            = "If-Range"
    HeaderRange                              = "Range"
    HeaderContentSecurityPolicy              = "Content-Security-Policy"
    HeaderContentSecurityPolicyReportOnly    = "Content-Security-Policy-Report-Only"
    HeaderCrossOriginResourcePolicy          = "Cross-Origin-Resource-Policy"
    HeaderExpectCT                           = "Expect-CT"
    HeaderFeaturePolicy                      = "Feature-Policy"
    HeaderPublicKeyPins                      = "Public-Key-Pins"
    HeaderPublicKeyPinsReportOnly            = "Public-Key-Pins-Report-Only"
    HeaderStrictTransportSecurity            = "Strict-Transport-Security"
    HeaderUpgradeInsecureRequests            = "Upgrade-Insecure-Requests"
    HeaderXContentTypeOptions                = "X-Content-Type-Options"
    HeaderXDownloadOptions                   = "X-Download-Options"
    HeaderXFrameOptions                      = "X-Frame-Options"
    HeaderXPoweredBy                         = "X-Powered-By"
    HeaderXXSSProtection                     = "X-XSS-Protection"
    HeaderLastEventID                        = "Last-Event-ID"
    HeaderNEL                                = "NEL"
    HeaderPingFrom                           = "Ping-From"
    HeaderPingTo                             = "Ping-To"
    HeaderReportTo                           = "Report-To"
    HeaderTE                                 = "TE"
    HeaderTrailer                            = "Trailer"
    HeaderTransferEncoding                   = "Transfer-Encoding"
    HeaderSecWebSocketAccept                 = "Sec-WebSocket-Accept"
    HeaderSecWebSocketExtensions             = "Sec-WebSocket-Extensions"
    HeaderSecWebSocketKey                    = "Sec-WebSocket-Key"
    HeaderSecWebSocketProtocol               = "Sec-WebSocket-Protocol"
    HeaderSecWebSocketVersion                = "Sec-WebSocket-Version"
    HeaderAcceptPatch                        = "Accept-Patch"
    HeaderAcceptPushPolicy                   = "Accept-Push-Policy"
    HeaderAcceptSignature                    = "Accept-Signature"
    HeaderAltSvc                             = "Alt-Svc"
    HeaderDate                               = "Date"
    HeaderIndex                              = "Index"
    HeaderLargeAllocation                    = "Large-Allocation"
    HeaderLink                               = "Link"
    HeaderPushPolicy                         = "Push-Policy"
    HeaderRetryAfter                         = "Retry-After"
    HeaderServerTiming                       = "Server-Timing"
    HeaderSignature                          = "Signature"
    HeaderSignedHeaders                      = "Signed-Headers"
    HeaderSourceMap                          = "SourceMap"
    HeaderUpgrade                            = "Upgrade"
    HeaderXDNSPrefetchControl                = "X-DNS-Prefetch-Control"
    HeaderXPingback                          = "X-Pingback"
    HeaderXRequestID                         = "X-Request-ID"
    HeaderXRequestedWith                     = "X-Requested-With"
    HeaderXRobotsTag                         = "X-Robots-Tag"
    HeaderXUACompatible                      = "X-UA-Compatible"
    HeaderAccessControlAllowPrivateNetwork   = "Access-Control-Allow-Private-Network"
    HeaderAccessControlRequestPrivateNetwork = "Access-Control-Request-Private-Network"
)
```
