--- title: ECMAScript 2026 specification approved | daily.dev description: ECMA International has approved ECMAScript 2026 (ES2026), the 17th edition of the JavaScript specification, on June 30. The new edition introduces several... canonical: https://daily.dev/posts/ecmascript-2026-specification-approved-3orzqhzl9 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: ECMAScript 2026 specification approved | daily.dev og:description: ECMA International has approved ECMAScript 2026 (ES2026), the 17th edition of the JavaScript specification, on June 30. The new edition introduces several... og:url: https://daily.dev/posts/ecmascript-2026-specification-approved-3orzqhzl9 og:image: https://api.daily.dev/og/posts/3ORZQHZl9.png og:image:alt: ECMAScript 2026 specification approved og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # ECMAScript 2026 specification approved **[InfoWorld](https://daily.dev/sources/infoworld)** · 1 min read · 184 upvotes · 13 comments ## Summary ECMA International has approved ECMAScript 2026 (ES2026), the 17th edition of the JavaScript specification, on June 30. The new edition introduces several additions: Math.sumPrecise for precise summation of iterables, Iterator.concat for sequencing iterators, Array.fromAsync for building arrays from async sources, Error.isError for identifying error objects, new Map and WeakMap prototype methods for default-value retrieval, Uint8Array methods for hex and base64 string conversion, a JSON.parse reviver parameter for accessing raw JSON source, and JSON.rawJSON for fine-grained control over JSON.stringify output. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What new methods does ECMAScript 2026 add to JavaScript? ECMAScript 2026, approved by ECMA International on June 30, adds Math.sumPrecise for precise summation of numbers with varying magnitude, Iterator.concat for sequencing iterators, Array.fromAsync for building arrays from async iterables, Error.isError for identifying error objects, default-value retrieval methods on Map.prototype and WeakMap.prototype, Uint8Array hex/base64 conversion methods, an enhanced JSON.parse reviver parameter, and JSON.rawJSON. _Track new JavaScript spec features like these as they land by following ECMAScript updates on daily.dev._ ### How do I sum an array of numbers in JavaScript without losing precision for very large or very small values? Use Math.sumPrecise, a new method introduced in ECMAScript 2026 that sums an iterable of numbers of varying magnitude while minimizing precision loss, addressing a common floating-point summation accuracy problem in JavaScript. _Developers chasing floating-point precision bugs can keep up with JavaScript numeric method additions on daily.dev._ ### What does JSON.rawJSON do in JavaScript? JSON.rawJSON is a new ECMAScript 2026 feature that gives fine control over JSON.stringify output for primitive values, allowing a raw JSON representation to be embedded directly without the usual value serialization rules being applied. _Anyone fine-tuning JSON serialization behavior can follow JavaScript spec changes like this on daily.dev._ ## Community discussion Top comments from developers on daily.dev. **@friedrich** · 20 upvotes > Finally! `Error.isError` instead of `error instanceof Error` **@apperside** · 15 upvotes > Wow! Those things will definitely improve many aspects of our daily job. Can't wait to try them out **@luispsarmiento** · 2 upvotes >  **@danieljohnbyns** · 1 upvotes > wow! this is shit **@codexsavage6s** · 0 upvotes > Hmm ...🤔 The Array.fromAsync looks promising ## Similar posts on daily.dev - [ES2026 Solves JavaScript Headaches With Dates, Math and Modules](https://daily.dev/posts/es2026-solves-javascript-headaches-with-dates-math-and-modules-y1adbmp5d) · The New Stack · 171 upvotes · 2 comments - [JavaScript ES2026 is Less About New Syntax — and More About Writing Better Code](https://daily.dev/posts/javascript-es2026-is-less-about-new-syntax-and-more-about-writing-better-code-0zsgaegpc) · Medium · 1 upvotes · 0 comments - [Useful JavaScript Additions in ECMAScript 2026](https://daily.dev/posts/useful-javascript-additions-in-ecmascript-2026-0esitfen2) · Telerik · 19 upvotes · 2 comments - [What's actually new in JavaScript \(and what's coming next\)](https://daily.dev/posts/what-s-actually-new-in-javascript-and-what-s-coming-next--nffnrggpd) · Neciu Dan · 66 upvotes · 5 comments - [ES2026 Is Here: 10 Features That Halve Your JavaScript](https://daily.dev/posts/es2026-is-here-10-features-that-halve-your-javascript-jyussl4hc) · Medium · 3 upvotes · 1 comments --- Tags: [#webdev](https://daily.dev/tags/webdev), [#javascript](https://daily.dev/tags/javascript) [View this post on daily.dev](https://daily.dev/posts/ecmascript-2026-specification-approved-3orzqhzl9) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"ECMAScript 2026 specification approved","url":"https://daily.dev/posts/ecmascript-2026-specification-approved-3orzqhzl9","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/ecmascript-2026-specification-approved-3orzqhzl9"},"datePublished":"2026-07-07T03:28:53.072Z","dateModified":"2026-09-14T06:23:33.338Z","description":"ECMA International has approved ECMAScript 2026 (ES2026), the 17th edition of the JavaScript specification, on June 30. 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Error.isError instead of error instanceof Error","datePublished":"2026-07-07T11:43:26.747Z","url":"https://daily.dev/posts/3ORZQHZl9#c-om2lBKCVd","author":{"@type":"Person","name":"Friedrich WT","url":"https://daily.dev/friedrich","image":"https://avatars.githubusercontent.com/u/136119888?v=4"},"interactionStatistic":{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":20}},{"@type":"Comment","text":"Wow! Those things will definitely improve many aspects of our daily job. 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