generated: '2026-09-07'
method: searched
source: >-
  https://www.w3.org/policies/process/, https://www.w3.org/Style/CSS/current-work,
  https://www.w3.org/TR/css-2026/ and https://github.com/w3c/css-validator/releases
summary: >-
  CSS has two independent lifecycles and this record covers both. The specification lifecycle
  is the W3C Process maturity ladder, which every CSS module climbs and which defines what it
  means for a CSS feature to be stable, superseded or withdrawn. The service lifecycle is the
  CSS Validation Service, which is versioned only by dated source releases and carries no API
  version at all.
specification_lifecycle:
  authority: W3C Process Document
  url: https://www.w3.org/policies/process/
  stages:
    - {code: FPWD, name: First Public Working Draft, stable: false}
    - {code: WD, name: Working Draft, stable: false}
    - {code: ED, name: Editor's Draft, stable: false, note: Not a W3C publication stage; the working copy at drafts.csswg.org.}
    - {code: CRD, name: Candidate Recommendation Draft, stable: false}
    - {code: CR, name: Candidate Recommendation Snapshot, stable: partial, note: Feature-complete and open for implementation.}
    - {code: PR, name: Proposed Recommendation, stable: true}
    - {code: REC, name: Recommendation, stable: true}
    - {code: NOTE, name: Group Note, stable: false}
  current_distribution:
    note: >-
      Counted from vocabulary/css-all-properties.json, which is generated by W3C from the
      specifications themselves. Rows, not distinct properties — one property defined at two
      maturities counts twice.
    ED: 1239
    WD: 555
    CRD: 163
    REC: 161
    FPWD: 96
    CR: 58
    NOTE: 7
  current_work: https://www.w3.org/Style/CSS/current-work
deprecation_policy:
  published: true
  url: https://www.w3.org/policies/process/#rec-rescind
  summary: >-
    The W3C Process Document defines three end-of-life states for a Recommendation and the
    procedure for reaching each: Superseded (a newer Recommendation replaces it), Obsolete
    (the Consortium no longer endorses it, though it may still be widely deployed), and
    Rescinded (the Consortium withdraws it entirely). Candidate Recommendations can also be
    rescinded. Each transition requires a Proposed Rescinded/Obsolete Recommendation review
    period, so a CSS module cannot be withdrawn without public notice.
  states: [Superseded Recommendation, Obsolete Recommendation, Rescinded Recommendation, Rescinded Candidate Recommendation]
  anchors:
    - https://www.w3.org/policies/process/#rec-rescind
    - https://www.w3.org/policies/process/#obsolete
    - https://www.w3.org/policies/process/#superseded
  applies_to: CSS specifications, not the validation service
  http_signals:
    sunset_header: false
    deprecation_header: false
    note: >-
      RFC 8594 Sunset and Deprecation headers are not used anywhere in this record. Spec
      deprecation is announced in the TR document status section, not in a response header.
snapshots:
  note: >-
    The CSS Working Group publishes an annual CSS Snapshot defining which specifications make
    up "CSS" that year. This is the closest thing CSS has to a release train, and it is what a
    consumer should pin to rather than to individual module levels.
  current: {version: 'CSS Snapshot 2026', url: 'https://www.w3.org/TR/css-2026/', status: 200}
  recent:
    - {version: 'CSS Snapshot 2026', url: 'https://www.w3.org/TR/css-2026/'}
    - {version: 'CSS Snapshot 2025', url: 'https://www.w3.org/TR/css-2025/'}
    - {version: 'CSS Snapshot 2024', url: 'https://www.w3.org/TR/css-2024/'}
    - {version: 'CSS Snapshot 2023', url: 'https://www.w3.org/TR/css-2023/'}
service_lifecycle:
  api: W3C CSS Validation Service
  versioning: none
  detail: >-
    No version segment, no version header, no dated endpoints. The running build is whatever
    W3C has deployed; the DOWNLOAD page states the online service is a stable release
    generally older than the Git version and that results and behaviour may differ. A caller
    who needs a pinned engine is expected to self-host.
  release_scheme: dated source tags
  releases:
    - {tag: cssval-20250226, date: '2025-02-26'}
    - {tag: cssval-20231124, date: '2023-11-24'}
    - {tag: cssval-20220105, date: '2022-01-05'}
    - {tag: cssval-20211112, date: '2021-11-12'}
    - {tag: cssval-20211001, date: '2021-10-01'}
  source: https://github.com/w3c/css-validator/releases
  deprecated_operations: []
sla:
  published: false
  detail: >-
    None. The service is described as "a free, public service for all" with no availability
    commitment and no support contract.
status_page:
  url: https://status.w3.org/
  http_status: 200
  scope: W3C services
  note: >-
    W3C's own incident status page, live and subscribable by email and SMS. It covers W3C
    infrastructure generally; the static HTML does not enumerate the CSS Validator as a named
    component, so treat it as operator-level rather than service-level status.
support:
  mailing_list: https://lists.w3.org/Archives/Public/www-style/
  validator_feedback: mailto:www-validator-css@w3.org
  issues: https://github.com/w3c/csswg-drafts/issues