fetch | fetch() starts an asynchronous resource request and returns a promise for a Response. The promise can fulfill for HTTP error statuses, so inspect the response status before treating the request as successful. |
structuredClone | structuredClone() creates a deep clone of a structured-cloneable JavaScript value. Its optional transfer list can move transferable resources into the clone instead of copying them. |
BigInt | BigInt(value) converts a supported value into a primitive BigInt. It accepts integer-like values, strings, booleans, and BigInts, but rejects fractional Numbers and cannot be called with new. |
queueMicrotask | queueMicrotask() schedules a function as a microtask. The function runs after the current task completes, before control returns to the event loop. |
Object.entries | Object.entries() returns an array of [key, value] pairs for an object's own enumerable string-keyed properties. It excludes inherited properties and preserves the standard property-enumeration order. |
Object.fromEntries | Object.fromEntries() creates a new object from an iterable of key-value pairs. It accepts sources such as arrays and Maps, including entries with symbol keys. |
Promise.all | Promise.all() combines an iterable of promises or values into one promise. It fulfills with results in input order only when every item fulfills, and rejects as soon as an item rejects. |
Promise.allSettled | Promise.allSettled() waits for every input promise to settle and fulfills with an input-ordered array describing each result. It reports both successes and failures instead of rejecting because one input failed. |
Promise.race | Promise.race() returns a promise whose outcome follows the first item in an iterable to settle, whether fulfillment or rejection. It always settles asynchronously and remains pending when given an empty iterable. |
Array.from | Array.from() creates a new Array from an iterable or array-like object. An optional callback can transform each value as the result is built. |
map | Function |
filter | Function |
reduce | Function |
forEach | Array.prototype.forEach() invokes a callback once for each assigned array element in ascending-index order. It returns undefined and is mainly used to perform side effects. |
find | find() returns the first array element for which a testing callback returns a truthy value. If no element matches, it returns undefined. |
findIndex | Array.prototype.findIndex() returns the index of the first array element whose testing function returns a truthy value. It returns -1 when no element matches. |
some | Array.prototype.some() tests whether at least one array element satisfies a callback. It returns true on the first truthy result and otherwise returns false. |
every | Array.prototype.every() tests array elements with a predicate and returns true only if every visited element passes. It stops at the first failure and returns false; an empty array returns true. |
flat | Array.prototype.flat() creates a new array by recursively concatenating nested arrays up to a chosen depth. Without an argument, it flattens one level. |
flatMap | Array.prototype.flatMap() maps each array element and flattens each callback result by one level. It returns a new array and does not recursively flatten deeper nesting. |
includes | String.prototype.includes() performs a case-sensitive substring search and reports whether the requested text occurs in a string. It returns a boolean and accepts an optional starting position. |
slice | String.prototype.slice() returns a selected section of a string as a new string. The start is inclusive, the end is exclusive, and the original string remains unchanged. |
splice | splice() changes an array in place by removing, replacing, and/or inserting elements. It returns a new array containing the elements removed. |
concat | Array.prototype.concat() returns a new array formed from the calling array and supplied arrays or values. It does not mutate the source arrays and spreads array arguments only one level. |
join | Array.prototype.join() returns a new string made by concatenating an array's elements, separated by commas or a chosen string. It returns an empty string for an empty array. |
sort | Array.prototype.sort() sorts an array in place and returns the same array. By default it compares string representations in UTF-16 order; pass a comparator for custom ordering. |
reverse | Array.prototype.reverse() reverses an array in place and returns the same array reference. Use toReversed() or copy the array first when the original must remain unchanged. |
indexOf | Array.prototype.indexOf() returns the first index where a value occurs in an array, or -1 when it is absent. It optionally accepts a starting index and uses strict equality for matching. |
fill | Array.prototype.fill() replaces elements in a selected index range with one static value. It mutates the array and returns the modified array. |
at | Array.prototype.at() returns the element at a given integer index and supports negative indexes that count from the end. It returns undefined when the index is outside the array's bounds. |
split | String.prototype.split() searches a string for a separator and returns an array of the substrings between matches. The separator may be a string, regular expression, or custom object with Symbol.split; an optional limit caps the result length. |
replace | String.prototype.replace() returns a new string with matching text replaced. String patterns replace only the first occurrence; use a global regular expression or replaceAll() for all occurrences. |
replaceAll | String.prototype.replaceAll() returns a new string in which every match of a string or replacement pattern is replaced. It leaves the original string unchanged. |
trim | trim() returns a new string with whitespace and line terminators removed from both ends of the string. It leaves the original string unchanged. |
padStart | String.prototype.padStart() adds characters to the beginning of a string until it reaches a requested length. The optional padding text is repeated or truncated as needed. |
padEnd | String.prototype.padEnd() appends repeated and, if necessary, truncated filler so a string reaches a requested length. It leaves strings already at least that long unchanged. |
startsWith | String.prototype.startsWith() checks whether a string begins with a specified string and returns a boolean. An optional position lets the check begin at a later index. |
endsWith | Determines whether a string ends with a specified string and returns true or false. An optional end position lets you test a portion of the string. |
repeat | String.prototype.repeat() returns a new string containing the receiver repeated a specified number of times. The count is converted to an integer and invalid or excessive counts throw RangeError. |
matchAll | String.prototype.matchAll() returns an iterator over every match of a pattern in a string, including capture groups. Consume it with standard iteration tools such as for...of or Array.from(). |
Object.keys | Object.keys() returns an array of an object's own enumerable string-keyed property names. It excludes inherited and non-enumerable properties. |
Object.values | Object.values() returns an array of an object's own enumerable string-keyed property values. It excludes inherited and symbol-keyed properties. |
Object.assign | Object.assign() copies enumerable own properties from one or more sources into a target object. It mutates and returns the target, with later sources winning when keys overlap. |
Object.freeze | Object.freeze() prevents extensions and locks an object's existing properties. It returns the same object reference and does not recursively freeze nested objects. |
Object.create | Object.create() creates a new object with a chosen prototype. An optional descriptor map defines its own properties with precise attribute control. |
Object.defineProperty | Defines or modifies an object's own property with a descriptor, controlling its value, accessors, and property flags. On success, it returns the original object. |
Object.getPrototypeOf | Object.getPrototypeOf() returns the internal [[Prototype]] of a value. Its result is an object or null; modern JavaScript coerces primitive arguments to wrapper objects before retrieving the prototype. |
Math.max | Math.max() returns the greatest value among its arguments. It returns -Infinity with no arguments and NaN when any argument is or converts to NaN. |
Math.min | Math.min() returns the smallest of zero or more supplied values. It returns Infinity with no arguments and NaN if any argument is or converts to NaN. |
Math.round | Math.round() returns a number rounded to the nearest integer. Exact halves round toward positive infinity, so -3.5 becomes -3 and 3.5 becomes 4. |
Math.floor | Math.floor() returns the largest integer less than or equal to a number. Unlike truncation, it rounds negative fractional values toward negative infinity. |
Math.ceil | Math.ceil() returns the smallest integer greater than or equal to a number. It rounds toward positive infinity, so negative fractional values move toward zero. |
Math.random | Math.random() returns an approximately uniformly distributed pseudo-random floating-point number from 0 inclusive to 1 exclusive. It accepts no arguments and is not suitable for cryptographic security. |
Math.abs | Math.abs() returns the absolute value of a number. It converts its argument to a Number and returns a non-negative result, or NaN when conversion is not possible. |
Math.pow | Math.pow() returns a base raised to an exponent. It is a static Math method that accepts numeric arguments and returns a Number. |
Number.isInteger | Number.isInteger() tests whether a value is a Number representing an integer. It does not coerce non-number values and returns false for NaN and infinities. |
parseInt | parseInt() converts a value to a string and parses an integer in a specified radix. It returns the parsed integer or NaN when the radix is invalid or no initial numeric characters can be parsed. |
parseFloat | parseFloat() converts its argument to a string and parses the longest valid decimal-number prefix. It returns the resulting floating-point number, Infinity, or NaN when parsing cannot begin. |
isFinite | Number.isFinite() checks whether a value is a finite JavaScript number. It returns false for non-numbers, NaN, and positive or negative infinity. |
Promise.resolve | Promise.resolve(value) converts a value, promise, or thenable into a Promise. It reuses eligible existing promises, assimilates thenables, and fulfills with ordinary values. |
Promise.reject | Promise.reject() creates and returns a new promise that is already rejected with the supplied reason. It is useful for producing rejection branches or adapting a value into a rejected promise. |
Promise.any | Promise.any() returns a promise fulfilled by the first input that fulfills. It rejects with AggregateError when every input rejects, including an empty iterable. |
Promise.withResolvers | Promise.withResolvers() returns a new promise together with the resolve and reject functions that control it. This makes it convenient to settle a promise from code outside its constructor executor. |
Array.fromAsync | Array.fromAsync() builds a new array from an async iterable, iterable, or array-like object. It returns a promise and awaits source values and optional mapping results. |
Object.groupBy | Object.groupBy() groups an iterable's elements by keys returned from a callback. It returns a null-prototype object whose properties contain arrays of the original elements for each group. |
Map.groupBy | Map.groupBy() groups an iterable's elements by callback results and returns a Map from each group key to its matching elements. Unlike Object.groupBy(), it can use arbitrary object or primitive keys. |
String.raw | String.raw() creates a string from a template literal without interpreting its escape sequences. Interpolated expressions are still evaluated and inserted. |
Array.of | Array.of() creates a new array from its arguments, regardless of how many arguments there are or what types they have. A single number is stored as an element, unlike with Array(). |
Object.hasOwn | Object.hasOwn() returns whether an object contains a specified property as its own property. It excludes inherited properties and works with null-prototype objects. |