mdn.io

Avaliação do site mdn.io

JavaScript | MDN

 Gerado a 22 de Janeiro de 2026 11:25 AM

Estatísticas desatualizadas? ATUALIZE !

O resultado é de 49/100

Conteúdo SEO

Título

JavaScript | MDN

Cumprimento : 16

Perfeito, o Título contém entre 10 e 70 caracteres.

Descrição

JavaScript (JS) is a lightweight interpreted (or just-in-time compiled) programming language with first-class functions. While it is most well-known as the scripting language for Web pages, many non-browser environments also use it, such as Node.js, Apache CouchDB and Adobe Acrobat. JavaScript is a prototype-based, garbage-collected, dynamic language, supporting multiple paradigms such as imperative, functional, and object-oriented.

Cumprimento : 436

Idealmente, a Descrição META deve conter entre 70 e 160 caracteres (incluíndo espaços).

Palavras-chave

Mau. Não detetámos palavras-chave META na sua página.

Propriedades Og Meta

Esta página não tira vantagens das propriedades Og.

Cabeçalhos

H1 H2 H3 H4 H5 H6
1 5 3 0 0 0
  • [H1] JavaScript
  • [H2] In this article
  • [H2] Beginner's tutorials
  • [H2] JavaScript guides
  • [H2] Reference
  • [H2] Help improve MDN
  • [H3] Fundamental language guides
  • [H3] Intermediate
  • [H3] Advanced

Imagens

Encontrámos 0 imagens nesta página.

Bom, a maioria das imagens têm o atributo ALT definidos.

Rácio Texto/HTML

Rácio : 13%

O rácio de texto para código HTML desta página é menor que 15 porcento, o que significa que provavelmente é necessário de adicionar mais conteúdos em forma de texto.

Flash

Perfeito, não foi encontrado conteúdo Flash nesta página.

Iframe

Excelente, não foram detetadas Iframes nesta página.

Reescrita de URL

Perfeito. As ligações aparentam ser limpas!

Underscores (traços inferiores) nas URLs

Detetámos 'underscores' (traços inferiores) nas suas URLs. O uso hífens é mais eficiente em termos de otimização SEO.

Ligações para a própria página

Encontrámos um total de 450 ligações incluindo 12 ligações a ficheiros

Âncoras Tipo Sumo
Skip to main content Internas Passa sumo
Skip to search Internas Passa sumo
just-in-time compiled Internas Passa sumo
first-class functions Internas Passa sumo
many non-browser environments Externas Passa sumo
Node.js Internas Passa sumo
Apache CouchDB Externas Passa sumo
Adobe Acrobat Externas Passa sumo
prototype-based Internas Passa sumo
garbage-collected Internas Passa sumo
dynamic Internas Passa sumo
APIs Internas Passa sumo
Web APIs Internas Passa sumo
DOM Internas Passa sumo
ECMAScript Language Specification Externas Passa sumo
ECMAScript Internationalization API specification Externas Passa sumo
proposals for new ECMAScript features Externas Passa sumo
stages Externas Passa sumo
Java programming language Externas Passa sumo
ECMAScript Internas Passa sumo
JavaScript guide Internas Passa sumo
JavaScript reference Internas Passa sumo
Beginner's tutorials Internas Passa sumo
JavaScript guides Internas Passa sumo
Reference Internas Passa sumo
learn web development core modules Internas Passa sumo
Your first website: Adding interactivity Internas Passa sumo
Dynamic scripting with JavaScript Internas Passa sumo
JavaScript frameworks and libraries Internas Passa sumo
Fundamental language guides Internas Passa sumo
Intermediate Internas Passa sumo
Advanced JavaScript objects Internas Passa sumo
Asynchronous JavaScript Internas Passa sumo
asynchronous Internas Passa sumo
Client-side web APIs Internas Passa sumo
JavaScript language overview Internas Passa sumo
JavaScript data structures Internas Passa sumo
Equality comparisons and sameness Internas Passa sumo
Enumerability and ownership of properties Internas Passa sumo
Closures Internas Passa sumo
Advanced Internas Passa sumo
Inheritance and the prototype chain Internas Passa sumo
Memory Management Internas Passa sumo
Standard objects Internas Passa sumo
Expressions and operators Internas Passa sumo
operator precedence Internas Passa sumo
Statements and declarations Internas Passa sumo
Functions Internas Passa sumo
Classes Internas Passa sumo
MDN contributors Internas Passa sumo
JavaScript Internas Passa sumo
Introduction Internas Passa sumo
Grammar and types Internas Passa sumo
Control flow and error handling Internas Passa sumo
Loops and iteration Internas Passa sumo
Functions Internas Passa sumo
Expressions and operators Internas Passa sumo
Numbers and strings Internas Passa sumo
Representing dates & times Internas Passa sumo
Regular expressions Internas Passa sumo
Indexed collections Internas Passa sumo
Keyed collections Internas Passa sumo
Working with objects Internas Passa sumo
Using classes Internas Passa sumo
Using promises Internas Passa sumo
JavaScript typed arrays Internas Passa sumo
Iterators and generators Internas Passa sumo
Resource management Internas Passa sumo
Internationalization Internas Passa sumo
JavaScript modules Internas Passa sumo
Meta programming Internas Passa sumo
AggregateError Internas Passa sumo
Array Internas Passa sumo
ArrayBuffer Internas Passa sumo
AsyncDisposableStack Internas Passa sumo
AsyncFunction Internas Passa sumo
AsyncGenerator Internas Passa sumo
AsyncGeneratorFunction Internas Passa sumo
AsyncIterator Internas Passa sumo
Atomics Internas Passa sumo
BigInt Internas Passa sumo
BigInt64Array Internas Passa sumo
BigUint64Array Internas Passa sumo
Boolean Internas Passa sumo
DataView Internas Passa sumo
Date Internas Passa sumo
decodeURI() Internas Passa sumo
decodeURIComponent() Internas Passa sumo
DisposableStack Internas Passa sumo
encodeURI() Internas Passa sumo
encodeURIComponent() Internas Passa sumo
Error Internas Passa sumo
escape() Internas Passa sumo
eval() Internas Passa sumo
EvalError Internas Passa sumo
FinalizationRegistry Internas Passa sumo
Float16Array Internas Passa sumo
Float32Array Internas Passa sumo
Float64Array Internas Passa sumo
Function Internas Passa sumo
Generator Internas Passa sumo
GeneratorFunction Internas Passa sumo
globalThis Internas Passa sumo
Infinity Internas Passa sumo
Int8Array Internas Passa sumo
Int16Array Internas Passa sumo
Int32Array Internas Passa sumo
InternalError Internas Passa sumo
Intl Internas Passa sumo
isFinite() Internas Passa sumo
isNaN() Internas Passa sumo
Iterator Internas Passa sumo
JSON Internas Passa sumo
Map Internas Passa sumo
Math Internas Passa sumo
NaN Internas Passa sumo
Number Internas Passa sumo
Object Internas Passa sumo
parseFloat() Internas Passa sumo
parseInt() Internas Passa sumo
Promise Internas Passa sumo
Proxy Internas Passa sumo
RangeError Internas Passa sumo
ReferenceError Internas Passa sumo
Reflect Internas Passa sumo
RegExp Internas Passa sumo
Set Internas Passa sumo
SharedArrayBuffer Internas Passa sumo
String Internas Passa sumo
SuppressedError Internas Passa sumo
Symbol Internas Passa sumo
SyntaxError Internas Passa sumo
Temporal Internas Passa sumo
TypedArray Internas Passa sumo
TypeError Internas Passa sumo
Uint8Array Internas Passa sumo
Uint8ClampedArray Internas Passa sumo
Uint16Array Internas Passa sumo
Uint32Array Internas Passa sumo
undefined Internas Passa sumo
unescape() Internas Passa sumo
URIError Internas Passa sumo
WeakMap Internas Passa sumo
WeakRef Internas Passa sumo
WeakSet Internas Passa sumo
Addition (+) Internas Passa sumo
Addition assignment (+=) Internas Passa sumo
Assignment (=) Internas Passa sumo
async function expression Internas Passa sumo
async function* expression Internas Passa sumo
await Internas Passa sumo
Bitwise AND (&) Internas Passa sumo
Bitwise AND assignment (&=) Internas Passa sumo
Bitwise NOT (~) Internas Passa sumo
Bitwise OR (|) Internas Passa sumo
Bitwise OR assignment (|=) Internas Passa sumo
Bitwise XOR (^) Internas Passa sumo
Bitwise XOR assignment (^=) Internas Passa sumo
class expression Internas Passa sumo
Comma operator (,) Internas Passa sumo
Conditional (ternary) operator Internas Passa sumo
Decrement (--) Internas Passa sumo
delete Internas Passa sumo
Destructuring Internas Passa sumo
Division (/) Internas Passa sumo
Division assignment (/=) Internas Passa sumo
Equality (==) Internas Passa sumo
Exponentiation (**) Internas Passa sumo
Exponentiation assignment (**=) Internas Passa sumo
function expression Internas Passa sumo
function* expression Internas Passa sumo
Greater than (>) Internas Passa sumo
Greater than or equal (>=) Internas Passa sumo
Grouping operator ( ) Internas Passa sumo
import.meta Internas Passa sumo
import.meta.resolve() Internas Passa sumo
import() Internas Passa sumo
in Internas Passa sumo
Increment (++) Internas Passa sumo
Inequality (!=) Internas Passa sumo
instanceof Internas Passa sumo
Left shift (<<) Internas Passa sumo
Left shift assignment (<<=) Internas Passa sumo
Less than (<) Internas Passa sumo
Less than or equal (<=) Internas Passa sumo
Logical AND (&&) Internas Passa sumo
Logical AND assignment (&&=) Internas Passa sumo
Logical NOT (!) Internas Passa sumo
Logical OR (||) Internas Passa sumo
Logical OR assignment (||=) Internas Passa sumo
Multiplication (*) Internas Passa sumo
Multiplication assignment (*=) Internas Passa sumo
new Internas Passa sumo
new.target Internas Passa sumo
null Internas Passa sumo
Nullish coalescing assignment (??=) Internas Passa sumo
Nullish coalescing operator (??) Internas Passa sumo
Object initializer Internas Passa sumo
Optional chaining (?.) Internas Passa sumo
Property accessors Internas Passa sumo
Remainder (%) Internas Passa sumo
Remainder assignment (%=) Internas Passa sumo
Right shift (>>) Internas Passa sumo
Right shift assignment (>>=) Internas Passa sumo
Spread syntax (...) Internas Passa sumo
Strict equality (===) Internas Passa sumo
Strict inequality (!==) Internas Passa sumo
Subtraction (-) Internas Passa sumo
Subtraction assignment (-=) Internas Passa sumo
super Internas Passa sumo
this Internas Passa sumo
typeof Internas Passa sumo
Unary negation (-) Internas Passa sumo
Unary plus (+) Internas Passa sumo
Unsigned right shift (>>>) Internas Passa sumo
Unsigned right shift assignment (>>>=) Internas Passa sumo
void operator Internas Passa sumo
yield Internas Passa sumo
yield* Internas Passa sumo
async function Internas Passa sumo
async function* Internas Passa sumo
await using Internas Passa sumo
Block statement Internas Passa sumo
break Internas Passa sumo
class Internas Passa sumo
const Internas Passa sumo
continue Internas Passa sumo
debugger Internas Passa sumo
do...while Internas Passa sumo
Empty statement Internas Passa sumo
export Internas Passa sumo
Expression statement Internas Passa sumo
for Internas Passa sumo
for await...of Internas Passa sumo
for...in Internas Passa sumo
for...of Internas Passa sumo
function Internas Passa sumo
function* Internas Passa sumo
if...else Internas Passa sumo
import Internas Passa sumo
Import attributes Internas Passa sumo
Labeled statement Internas Passa sumo
let Internas Passa sumo
return Internas Passa sumo
switch Internas Passa sumo
throw Internas Passa sumo
try...catch Internas Passa sumo
using Internas Passa sumo
var Internas Passa sumo
while Internas Passa sumo
with Internas Passa sumo
Arrow function expressions Internas Passa sumo
Default parameters Internas Passa sumo
get Internas Passa sumo
Method definitions Internas Passa sumo
Rest parameters Internas Passa sumo
set Internas Passa sumo
The arguments object Internas Passa sumo
[Symbol.iterator]() Internas Passa sumo
callee Internas Passa sumo
length Internas Passa sumo
constructor Internas Passa sumo
extends Internas Passa sumo
Private elements Internas Passa sumo
Public class fields Internas Passa sumo
static Internas Passa sumo
Static initialization blocks Internas Passa sumo
Regular expressions Internas Passa sumo
Backreference: \1, \2 Internas Passa sumo
Capturing group: (...) Internas Passa sumo
Character class escape: \d, \D, \w, \W, \s, \S Internas Passa sumo
Character class: [...], [^...] Internas Passa sumo
Character escape: \n, \u{...} Internas Passa sumo
Disjunction: | Internas Passa sumo
Input boundary assertion: ^, $ Internas Passa sumo
Literal character: a, b Internas Passa sumo
Lookahead assertion: (?=...), (?!...) Internas Passa sumo
Lookbehind assertion: (?<=...), (?<!...) Internas Passa sumo
Modifier: (?ims-ims:...) Internas Passa sumo
Named backreference: \k<name> Internas Passa sumo
Named capturing group: (?<name>...) Internas Passa sumo
Non-capturing group: (?:...) Internas Passa sumo
Quantifier: *, +, ?, {n}, {n,}, {n,m} Internas Passa sumo
Unicode character class escape: \p{...}, \P{...} Internas Passa sumo
Wildcard: . Internas Passa sumo
Word boundary assertion: \b, \B Internas Passa sumo
Errors Internas Passa sumo
AggregateError: No Promise in Promise.any was resolved Internas Passa sumo
Error: Permission denied to access property "x" Internas Passa sumo
InternalError: too much recursion Internas Passa sumo
RangeError: argument is not a valid code point Internas Passa sumo
RangeError: BigInt division by zero Internas Passa sumo
RangeError: BigInt negative exponent Internas Passa sumo
RangeError: form must be one of 'NFC', 'NFD', 'NFKC', or 'NFKD' Internas Passa sumo
RangeError: invalid array length Internas Passa sumo
RangeError: invalid date Internas Passa sumo
RangeError: precision is out of range Internas Passa sumo
RangeError: radix must be an integer Internas Passa sumo
RangeError: repeat count must be less than infinity Internas Passa sumo
RangeError: repeat count must be non-negative Internas Passa sumo
RangeError: x can't be converted to BigInt because it isn't an integer Internas Passa sumo
ReferenceError: "x" is not defined Internas Passa sumo
ReferenceError: assignment to undeclared variable "x" Internas Passa sumo
ReferenceError: can't access lexical declaration 'X' before initialization Internas Passa sumo
ReferenceError: must call super constructor before using 'this' in derived class constructor Internas Passa sumo
ReferenceError: super() called twice in derived class constructor Internas Passa sumo
SyntaxError: 'arguments'/'eval' can't be defined or assigned to in strict mode code Internas Passa sumo
SyntaxError: "0"-prefixed octal literals are deprecated Internas Passa sumo
SyntaxError: "use strict" not allowed in function with non-simple parameters Internas Passa sumo
SyntaxError: "x" is a reserved identifier Internas Passa sumo
SyntaxError: \ at end of pattern Internas Passa sumo
SyntaxError: a declaration in the head of a for-of loop can't have an initializer Internas Passa sumo
SyntaxError: applying the 'delete' operator to an unqualified name is deprecated Internas Passa sumo
SyntaxError: arguments is not valid in fields Internas Passa sumo
SyntaxError: await is only valid in async functions, async generators and modules Internas Passa sumo
SyntaxError: await/yield expression can't be used in parameter Internas Passa sumo
SyntaxError: cannot use `??` unparenthesized within `||` and `&&` expressions Internas Passa sumo
SyntaxError: character class escape cannot be used in class range in regular expression Internas Passa sumo
SyntaxError: continue must be inside loop Internas Passa sumo
SyntaxError: duplicate capture group name in regular expression Internas Passa sumo
SyntaxError: duplicate formal argument x Internas Passa sumo
SyntaxError: for-in loop head declarations may not have initializers Internas Passa sumo
SyntaxError: function statement requires a name Internas Passa sumo
SyntaxError: functions cannot be labelled Internas Passa sumo
SyntaxError: getter and setter for private name #x should either be both static or non-static Internas Passa sumo
SyntaxError: getter functions must have no arguments Internas Passa sumo
SyntaxError: identifier starts immediately after numeric literal Internas Passa sumo
SyntaxError: illegal character Internas Passa sumo
SyntaxError: import declarations may only appear at top level of a module Internas Passa sumo
SyntaxError: incomplete quantifier in regular expression Internas Passa sumo
SyntaxError: invalid assignment left-hand side Internas Passa sumo
SyntaxError: invalid BigInt syntax Internas Passa sumo
SyntaxError: invalid capture group name in regular expression Internas Passa sumo
SyntaxError: invalid character in class in regular expression Internas Passa sumo
SyntaxError: invalid class set operation in regular expression Internas Passa sumo
SyntaxError: invalid decimal escape in regular expression Internas Passa sumo
SyntaxError: invalid identity escape in regular expression Internas Passa sumo
SyntaxError: invalid named capture reference in regular expression Internas Passa sumo
SyntaxError: invalid property name in regular expression Internas Passa sumo
SyntaxError: invalid range in character class Internas Passa sumo
SyntaxError: invalid regexp group Internas Passa sumo
SyntaxError: invalid regular expression flag "x" Internas Passa sumo
SyntaxError: invalid unicode escape in regular expression Internas Passa sumo
SyntaxError: JSON.parse: bad parsing Internas Passa sumo
SyntaxError: label not found Internas Passa sumo
SyntaxError: missing : after property id Internas Passa sumo
SyntaxError: missing ) after argument list Internas Passa sumo
SyntaxError: missing ) after condition Internas Passa sumo
SyntaxError: missing ] after element list Internas Passa sumo
SyntaxError: missing } after function body Internas Passa sumo
SyntaxError: missing } after property list Internas Passa sumo
SyntaxError: missing = in const declaration Internas Passa sumo
SyntaxError: missing formal parameter Internas Passa sumo
SyntaxError: missing name after . operator Internas Passa sumo
SyntaxError: missing variable name Internas Passa sumo
SyntaxError: negated character class with strings in regular expression Internas Passa sumo
SyntaxError: new keyword cannot be used with an optional chain Internas Passa sumo
SyntaxError: nothing to repeat Internas Passa sumo
SyntaxError: numbers out of order in {} quantifier. Internas Passa sumo
SyntaxError: octal escape sequences can't be used in untagged template literals or in strict mode code Internas Passa sumo
SyntaxError: parameter after rest parameter Internas Passa sumo
SyntaxError: private fields can't be deleted Internas Passa sumo
SyntaxError: property name __proto__ appears more than once in object literal Internas Passa sumo
SyntaxError: raw bracket is not allowed in regular expression with unicode flag Internas Passa sumo
SyntaxError: redeclaration of formal parameter "x" Internas Passa sumo
SyntaxError: reference to undeclared private field or method #x Internas Passa sumo
SyntaxError: rest parameter may not have a default Internas Passa sumo
SyntaxError: return not in function Internas Passa sumo
SyntaxError: setter functions must have one argument Internas Passa sumo
SyntaxError: string literal contains an unescaped line break Internas Passa sumo
SyntaxError: super() is only valid in derived class constructors Internas Passa sumo
SyntaxError: tagged template cannot be used with optional chain Internas Passa sumo
SyntaxError: Unexpected '#' used outside of class body Internas Passa sumo
SyntaxError: Unexpected token Internas Passa sumo
SyntaxError: unlabeled break must be inside loop or switch Internas Passa sumo
SyntaxError: unparenthesized unary expression can't appear on the left-hand side of '**' Internas Passa sumo
SyntaxError: use of super property/member accesses only valid within methods or eval code within methods Internas Passa sumo
SyntaxError: Using //@ to indicate sourceURL pragmas is deprecated. Use //# instead Internas Passa sumo
TypeError: 'caller', 'callee', and 'arguments' properties may not be accessed Internas Passa sumo
TypeError: 'x' is not iterable Internas Passa sumo
TypeError: "x" is (not) "y" Internas Passa sumo
TypeError: "x" is not a constructor Internas Passa sumo
TypeError: "x" is not a function Internas Passa sumo
TypeError: "x" is not a non-null object Internas Passa sumo
TypeError: "x" is read-only Internas Passa sumo
TypeError: already executing generator Internas Passa sumo
TypeError: BigInt value can't be serialized in JSON Internas Passa sumo
TypeError: calling a builtin X constructor without new is forbidden Internas Passa sumo
TypeError: can't access/set private field or method: object is not the right class Internas Passa sumo
TypeError: can't assign to property "x" on "y": not an object Internas Passa sumo
TypeError: can't convert BigInt to number Internas Passa sumo
TypeError: can't convert x to BigInt Internas Passa sumo
TypeError: can't define property "x": "obj" is not extensible Internas Passa sumo
TypeError: can't delete non-configurable array element Internas Passa sumo
TypeError: can't redefine non-configurable property "x" Internas Passa sumo
TypeError: can't set prototype of this object Internas Passa sumo
TypeError: can't set prototype: it would cause a prototype chain cycle Internas Passa sumo
TypeError: cannot use 'in' operator to search for 'x' in 'y' Internas Passa sumo
TypeError: class constructors must be invoked with 'new' Internas Passa sumo
TypeError: cyclic object value Internas Passa sumo
TypeError: derived class constructor returned invalid value x Internas Passa sumo
TypeError: getting private setter-only property Internas Passa sumo
TypeError: Initializing an object twice is an error with private fields/methods Internas Passa sumo
TypeError: invalid 'instanceof' operand 'x' Internas Passa sumo
TypeError: invalid Array.prototype.sort argument Internas Passa sumo
TypeError: invalid assignment to const "x" Internas Passa sumo
TypeError: Iterator/AsyncIterator constructor can't be used directly Internas Passa sumo
TypeError: matchAll/replaceAll must be called with a global RegExp Internas Passa sumo
TypeError: More arguments needed Internas Passa sumo
TypeError: null/undefined has no properties Internas Passa sumo
TypeError: property "x" is non-configurable and can't be deleted Internas Passa sumo
TypeError: Reduce of empty array with no initial value Internas Passa sumo
TypeError: setting getter-only property "x" Internas Passa sumo
TypeError: WeakSet key/WeakMap value 'x' must be an object or an unregistered symbol Internas Passa sumo
TypeError: X.prototype.y called on incompatible type Internas Passa sumo
URIError: malformed URI sequence Internas Passa sumo
Warning: -file- is being assigned a //# sourceMappingURL, but already has one Internas Passa sumo
Warning: unreachable code after return statement Internas Passa sumo
Execution model Internas Passa sumo
Lexical grammar Internas Passa sumo
Iteration protocols Internas Passa sumo
Strict mode Internas Passa sumo
Template literals Internas Passa sumo
Trailing commas Internas Passa sumo
Deprecated features Internas Passa sumo
- Externas Passa sumo
- Externas Passa sumo
- Externas Passa sumo
- Externas Passa sumo
- Internas Passa sumo
About Internas Passa sumo
Blog Internas Passa sumo
Mozilla careers Externas Passa sumo
Advertise with us Internas Passa sumo
MDN Plus Internas Passa sumo
Product help Externas Passa sumo
MDN Community Internas Passa sumo
Community resources Internas Passa sumo
Writing guidelines Internas Passa sumo
MDN Discord Internas Passa sumo
MDN on GitHub Externas Passa sumo
Web technologies Internas Passa sumo
Learn web development Internas Passa sumo
Guides Internas Passa sumo
Tutorials Internas Passa sumo
Glossary Internas Passa sumo
Hacks blog Externas Passa sumo
Mozilla Corporation’s Externas Passa sumo
Mozilla Foundation Externas Passa sumo
a Creative Commons license Internas Passa sumo

Palavras-chave SEO

Núvem de palavras-chave

invalid expression typeerror javascript regular class assignment object function syntaxerror

Consistência das Palavras-chave

Palavra-chave Conteúdo Título Palavras-chave Descrição Cabeçalhos
syntaxerror 73
javascript 44
typeerror 38
expression 22
class 19

Usabilidade

Url

Domínio : mdn.io

Cumprimento : 6

Favicon

Ótimo, o site tem um favicon.

Facilidade de Impressão

Não encontrámos CSS apropriado para impressão.

Língua

Otimo! A língua declarada deste site é en.

Dublin Core

Esta página não tira vantagens do Dublin Core.

Documento

Tipo de Documento

HTML 5

Codificação

Perfeito. O conjunto de caracteres UTF-8 está declarado.

Validação W3C

Erros : 0

Avisos : 0

Privacidade do Email

Boa! Nenhum endereço de email está declarado sob a forma de texto!

HTML obsoleto

Fantástico! Não detetámos etiquetas HTML obsoletas.

Dicas de Velocidade

Excelente, este site não usa tablelas dentro de tabelas.
Oh não, o site usa estilos CSS nas etiquetas HTML.
Oh, não! O site utiliza demasiados ficheiros CSS (mais que 4).
Perfeito, o site usa poucos ficheiros JavaScript.
Atenção, o site não tira vantagem da compressão gzip.

Dispositivos Móveis

Otimização para dispositivos móveis

Icon Apple
Meta Viewport Tag
Conteúdo Flash

Otimização

XML Sitemap

Perfeito, o site tem um mapa XML do site (sitemap).

https://duckduckgo.com/?q=%21%20site%3Adeveloper.mozilla.org%20sitemap.xml

Robots.txt

https://mdn.io/robots.txt

Perfeito, o seu site tem um ficheiro robots.txt.

Analytics

Em falta

Não detetámos nenhuma ferramenta analítica de análise de atividade.

Este tipo de ferramentas (como por exemplo o Google Analytics) permite perceber o comportamento dos visitantes e o tipo de atividade que fazem. No mínimo, uma ferramenta deve estar instalada, sendo que em algumas situações mais do que uma pode ser útil.

PageSpeed Insights

Dispositivo
Categorias

Free SEO Testing Tool

Free SEO Testing Tool é uma ferramenta gratuita que o ajuda a avaliar o seu site