TC39
TC39 (Ecma International Technical Committee 39) is a nonprofit technical standards committee that maintains and evolves the ECMAScript (JavaScript) language specifications, including ECMA-262, ECMA-402, ECMA-404, and ECMA-414, serving JavaScript developers, engine implementers, and academia globally.
- Company typePrivate
- Founded-
- Headquarters—
- Headcount1–10
- GTM typeB2B
- OfferingSoftware
What TC39 does
TC39 (Ecma International Technical Committee 39) is a nonprofit technical standards committee operating under Ecma International, headquartered in Geneva, Switzerland. TC39 is responsible for maintaining and evolving the ECMAScript specification — the formal definition of JavaScript — through a structured six-stage proposal process. Its core deliverables include ECMA-262 (the ECMAScript Language Specification), ECMA-402 (the Internationalization API Specification covering objects such as Intl.NumberFormat, Intl.DateTimeFormat, Intl.PluralRules, and Intl.Segmenter), ECMA-404 (the JSON Data Interchange Syntax specification), and ECMA-414 (the ECMAScript Specification Suite that bundles the others). The committee also maintains Test262, the comprehensive conformance test suite used by engine implementers to verify specification compliance.
The committee is composed of JavaScript developers, browser engine implementers, academics, and other stakeholders who collaborate publicly on GitHub, where all specification text, proposals, meeting agendas, and minutes are maintained. TC39 meets every two months to discuss and advance proposals through Stages 0–4 of its governance process, with proposals requiring implementation experience, test coverage, and specification text before advancing to standardization.
TC39 does not generate commercial revenue. All specifications are distributed freely through tc39.es and GitHub repositories, and participation is open to the public via community feedback channels (GitHub, Discourse, Bluesky, Mastodon, Matrix) or formally via Ecma International membership. TC39-TG2 is the dedicated technical subgroup for ECMA-402, convened by Shane F. Carr with editors from Igalia and the broader community. The committee's primary beneficiaries are JavaScript developers writing code for web, server (Node.js, Deno, Bun), mobile, desktop, and embedded platforms, as well as JavaScript engine implementers at Google (V8), Mozilla (SpiderMonkey), and Apple (JavaScriptCore), plus academic researchers studying programming language semantics.
TC39 firmographics
Firmographics- Name
- TC39
- Legal name
- TC39 (Technical Committee 39) - Ecma International
- Website
- https://tc39.es
- Company type
- Private
- Operating status
- Operating
- Headcount range
- 1–10 employees
- Short description
- TC39 (Ecma International Technical Committee 39) is a nonprofit technical standards committee that maintains and evolves the ECMAScript (JavaScript) language specifications, including ECMA-262, ECMA-402, ECMA-404, and ECMA-414, serving JavaScript developers, engine implementers, and academia globally.
- Ownership category
- akta.pro rank
TC39 industry classification
Industry- Product category
- Programming Language Standards
- NAICS
- Computer Systems Design and Related Services (54151)
- SIC
- Services-Computer Programming, Data Processing, Etc. (7370)
- akta.pro primary industry
- Conformity Assessment, Testing, Inspection & Certification Cooperation (BPADANAD)
Keywords
TC39 business model
Business model- GTM type
- B2B
- Offering type
- Software
- Cost components
- Personnel, Operations, Technology or R&D
Distribution channels2 records
Marketing channels4 records
TC39 product offering
Product offeringCore offering
TC39 is a technical committee of Ecma International that develops and maintains the official ECMAScript (JavaScript) language specification and related standards. It produces ECMA-262 (ECMAScript Language Specification), ECMA-402 (Internationalization API Specification), ECMA-404 (JSON Data Interchange Syntax), and ECMA-414 (ECMAScript Specification Suite), alongside the Test262 conformance test suite. The committee operates a six-stage proposal process and meets every two months to advance language features developed collaboratively on GitHub.
Product overview
TC39 (Ecma International Technical Committee 39) is a standards committee responsible for maintaining and evolving the ECMAScript specification (JavaScript). TC39 does not produce commercial products; instead, it develops open specifications including ECMA-262 (the core ECMAScript language specification), ECMA-402 (the Internationalization API specification with objects like Intl.Collator, Intl.DateTimeFormat, Intl.NumberFormat, Intl.Locale, and others), ECMA-404 (JSON specification), and ECMA-414 (specification suite bundling the others). The committee also maintains active proposals at various stages of development, representing potential future language features. TC39 operates through a structured six-stage proposal process, meeting every two months to discuss and advance proposals. Development and collaboration occur publicly on GitHub.
Differentiator
Problem solved
Functional benefit
Brands
- ECMA-262 (ECMAScript): The ECMAScript Language Specification - the official standard for JavaScript
- ECMA-402 (Intl API)
- ECMA-404
- ECMA-414
Products and services
- ECMA-262 (ECMAScript Language Specification)
- ECMA-402 (Internationalization API Specification) Provides internationalization functionality complementing ECMA-262, including Intl.Collator, Intl.DateTimeFormat, Intl.NumberFormat, Intl.Locale, Intl.ListFormat, Intl.DisplayNames, Intl.DurationFormat, Intl.PluralRules, Intl.RelativeTimeFormat, and Intl.Segmenter. Serves JavaScript engine implementers and developers building locale-aware applications.
- ECMA-404 (JSON Specification) Specification defining the JSON (JavaScript Object Notation) data interchange format. Used by software developers, language implementers, and tools across the software industry for data interchange.
- ECMA-414 (ECMAScript Specification Suite) A set of ECMAScript specifications bundled together, including ECMA-262, ECMA-402, and optionally ECMA-404. Provides implementers and adopters a consolidated reference for the ECMAScript standards.
- Test262 (ECMAScript Test Suite) A comprehensive test suite for ECMAScript implementations to verify conformance with ECMA-262 specifications. Used by JavaScript engine implementers to verify specification compliance.
Companies that use TC39
Customer profileSegments3 records
Ideal customer profiles3 records
TC39 technology and API
TechnologyTechnology focussed Yes
API detail
- Has API
- No
- API docs
- API detail
Core technology
AI maturity
App detail
Feature4 records
TC39 partnerships and signals
Strategic signalScale indicators3 records
Recent moves6 records
Expansion highlights4 records
TC39 competitors and assessment
Company assessmentDirect peers
- WHATWG: The Web Hypertext Application Technology Working Group maintains the HTML, DOM, and Fetch living standards — a comparable community/vendor-driven standards body operating alongside TC39 in defining web platform behavior.
- IETF (Internet Engineering Task Force): Develops internet standards (TCP/IP, HTTP/3, TLS) through an open, consensus-based, vendor-neutral process — directly comparable to TC39's model for evolving critical web infrastructure standards.
- Rust Foundation: The nonprofit stewarding the Rust programming language's evolution through RFCs and the Rust language team — comparable as a community/governance body for a modern programming language standard.
- Unicode Consortium: Maintains the Unicode Standard and CLDR (locale data), which TC39's ECMA-402 internationalization specification depends on. Operates a comparable nonprofit, member-driven model for cross-platform text and locale standardization.
- Ecma International (TC52 / TC53 / TC56): TC39's parent organization and sibling technical committees (e.g., TC52 for Dart, TC53 for ECMA-419 / IoT, TC56 for FiberChannel) operate under the same Ecma governance structure and standardization process.
- Python Software Foundation: The nonprofit that stewards Python's evolution through PEPs (Python Enhancement Proposals) — directly analogous to TC39's proposal process, governing a major programming language via an open community process.
- W3C (World Wide Web Consortium): The primary international standards organization for the World Wide Web, producing recommendations for CSS, SVG, and web APIs. Operates a similar consensus-based, multi-stakeholder model for web technology standardization.
Emerging players
- OpenJS Foundation: Hosts Node.js, jQuery, and other JavaScript ecosystem projects under the Linux Foundation. Adjacent to TC39 because its hosted projects implement ECMAScript and depend on TC39's specifications, with overlapping community governance.
Broad incumbents
- Khronos Group: Maintains open standards for graphics, compute, and ML (WebGL, Vulkan, SPIR-V). Operates a comparable multi-member, consensus-based process for evolving technical specifications adopted across implementations.
- ISO/IEC JTC 1: The joint ISO/IEC technical committee that oversees international IT standards, including adopted versions of ECMAScript (ISO/IEC 22275). Comparable in scope as the formal international standardization body for programming languages.
Market position
Strengths4 records
Weaknesses4 records
Competitive moat5 records
Key risks5 records
Key highlights6 records
Customer concentration
TC39 social profiles
Digital presenceTC39 financial estimates
Financial estimateRevenue estimate
Valuation estimate
TC39 leadership team
Management profileNumber of profiles
Profiles4 records
TC39 funding detail
Funding detailFunding overview
Funding rounds
Investors
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TC39 M&A and investment
M&A and investmentM&A
Investments
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Frequently asked questions about TC39
What does TC39 do?
TC39 is a technical committee of Ecma International that develops and maintains the official ECMAScript (JavaScript) language specification and related standards. It produces ECMA-262 (ECMAScript Language Specification), ECMA-402 (Internationalization API Specification), ECMA-404 (JSON Data Interchange Syntax), and ECMA-414 (ECMAScript Specification Suite), alongside the Test262 conformance test suite. The committee operates a six-stage proposal process and meets every two months to advance language features developed collaboratively on GitHub.
Is TC39 a public or private company?
TC39 is a private company. It is classified as nonprofit foundation owned and is currently operating.
When was TC39 founded?
TC39 was founded in -1. It employs 1 to 10 people.
Who are TC39's main competitors?
Direct peers on record are WHATWG, IETF (Internet Engineering Task Force), Rust Foundation, Unicode Consortium, Ecma International (TC52 / TC53 / TC56), Python Software Foundation and W3C (World Wide Web Consortium). OpenJS Foundation is listed as an emerging player. Broad incumbents are Khronos Group and ISO/IEC JTC 1.
Does TC39 have an API?
No public API is recorded for TC39.
What industry is TC39 in?
TC39's product category is Programming Language Standards. Its primary akta.pro industry code is BPADANAD, Conformity Assessment, Testing, Inspection & Certification Cooperation. Its NAICS code is 54151 and its SIC code is 7370.