specification: API Commons Rate Limits
specificationVersion: '0.1'
schema: https://raw.githubusercontent.com/api-evangelist/interface-research/main/schema/api-commons.yml#/$defs/RateLimits
provider: Google PageSpeed
providerId: google-pagespeed
created: '2026-05-04'
modified: '2026-08-13'
generated: '2026-08-13'
method: probed
source: >-
  Live unauthenticated GET of
  https://www.googleapis.com/pagespeedonline/v5/runPagespeed on 2026-08-13, plus a docs
  sweep of developers.google.com/speed/docs/insights
limit_count: 0
tags:
  - Core Web Vitals
  - Google
  - Lighthouse
  - Page Speed
  - SEO
  - Web Performance
  - Rate Limiting
  - Quotas
description: >-
  Google publishes NO numeric rate limit or quota for the PageSpeed Insights API on any
  public documentation page. limit_count is 0 for that reason. What the API does expose
  is the quota machinery itself, in the 429 body — the metric name, the limit name and
  the unit — which was captured live and is recorded below. The numeric value of
  defaultPerDayPerProject is only visible on the Cloud Console quotas page for
  pagespeedonline.googleapis.com, which requires a signed-in Google account. Widely
  repeated third-party figures (25,000 queries/day, 240 queries/minute) are NOT recorded
  here because Google does not publish them.
headers:
  limit: null
  remaining: null
  reset: null
  retryAfter: null
  policy: null
  observed: []
  finding: >-
    No X-RateLimit-*, RateLimit-* or Retry-After header is returned, on a successful
    response or on a 429. Response headers observed live were vary, content-type,
    server (ESF) and alt-svc only. An agent gets zero runtime budget signal and must back
    off blind.
responseCodes:
  throttled: 429
  quotaExceeded: 429
  serviceUnavailable: 503
error_signature:
  status: 429
  google_status: RESOURCE_EXHAUSTED
  reason: RATE_LIMIT_EXCEEDED
  legacy_reason: rateLimitExceeded
  message_observed: >-
    Quota exceeded for quota metric 'Queries' and limit 'Queries per day' of service
    'pagespeedonline.googleapis.com' for consumer 'project_number:...'
  help_link: https://cloud.google.com/docs/quotas/help/request_increase
  see: errors/google-pagespeed-problem-types.yml
limits: []
quota_surface:
  - name: defaultPerDayPerProject
    metric: pagespeedonline.googleapis.com/default
    display_metric: Queries
    display_limit: Queries per day
    unit: 1/d/{project}
    location: global
    scope: per-project
    value: null
    value_source: https://console.cloud.google.com/apis/api/pagespeedonline.googleapis.com/quotas
    value_note: >-
      Numeric value not published publicly; the Cloud Console quotas page is
      authentication-gated. Recorded as null rather than guessed.
    evidence: live 429 body, 2026-08-13
anonymous_access:
  keyless_quota_value_observed: '0'
  finding: >-
    An unkeyed request is charged against a shared anonymous pool whose observed
    quota_limit_value was "0" — every unkeyed call 429s immediately. The documentation
    calls the API key optional; in practice it is required.
policies:
  - name: Backoff Strategy
    description: >-
      Exponential backoff with jitter is the only viable strategy, because no Retry-After
      or reset header is returned to time the retry against.
  - name: Quota Attribution
    description: >-
      The `quotaUser` system parameter lets a caller attribute quota to an opaque
      end-user string when no Google user id is available, so one shared key can be
      apportioned across callers.
  - name: Quota Increase
    description: >-
      Increases are requested through Cloud Console quotas, per the google.rpc.Help link
      returned in the 429 body.
supersedes:
  note: >-
    This file replaces a 2026-05-04 bulk-sweep scaffold that invented free/professional/
    enterprise tiers, per-minute limits and burst ceilings, and asserted X-RateLimit-*
    headers this API does not send. See roadmap#35.
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com