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: microsoft-azure-cdn
providerId: microsoft-azure-cdn
generated: '2026-09-17'
method: searched
source: https://learn.microsoft.com/en-us/azure/azure-resource-manager/management/request-limits-and-throttling
created: '2026-05-04'
modified: '2026-09-17'
tags:
  - Rate Limiting
  - Quotas
  - Throttling
description: >-
  Published throttling limits for the Azure CDN management API. This REPLACES the 2026-05-04 API
  Evangelist scaffold, which invented free/professional/enterprise request quotas and X-RateLimit-*
  headers that Azure does not emit. The real mechanism is Azure Resource Manager's token-bucket
  throttling, applied per region, per subscription, per service principal and per operation type — the
  Microsoft.Cdn resource provider inherits it. Limits and header names below are read verbatim from the
  Microsoft ARM throttling documentation.
limit_count: 6
algorithm: token bucket — a bucket size (maximum burst) plus a per-second refill rate, applied per region
scope_note: >-
  Subscription limits apply per subscription, per service principal, and per operation type. Global
  subscription limits are 15x the individual service-principal limit for each operation type and apply
  across all service principals; a request is throttled if the global, service-principal or tenant limit
  is exceeded. Limits may be smaller for free or trial subscriptions.
headers:
  remaining:
    - x-ms-ratelimit-remaining-subscription-reads
    - x-ms-ratelimit-remaining-subscription-writes
    - x-ms-ratelimit-remaining-subscription-deletes
    - x-ms-ratelimit-remaining-subscription-resource-requests
    - x-ms-ratelimit-remaining-subscription-resource-entities-read
    - x-ms-ratelimit-remaining-tenant-reads
    - x-ms-ratelimit-remaining-tenant-writes
    - x-ms-ratelimit-remaining-tenant-resource-requests
    - x-ms-ratelimit-remaining-tenant-resource-entities-read
  retryAfter: Retry-After
  note: >-
    The remaining-count header returned depends on the operation: a read returns the reads header, a
    write the writes header, a delete the deletes header. Azure emits NO X-RateLimit-Limit,
    X-RateLimit-Reset or RateLimit-Policy header — an agent gets a remaining count and, on exhaustion,
    a Retry-After, and nothing else.
responseCodes:
  throttled: 429
  note: >-
    "When you reach the limit, you receive the HTTP status code 429 Too many requests. The response
    includes a Retry-After value, which specifies the number of seconds your application should wait
    before sending the next request. If you send a request before the retry value elapses, your request
    isn't processed and a new retry value is returned."
limits:
  - name: Subscription reads
    scope: subscription (per service principal, per region)
    metric: requests
    limit: 250
    burst: 250
    refill_per_second: 25
    timeFrame: second
    applies:
      - Azure CDN Management API (Microsoft.Cdn) — all GET operations
  - name: Subscription writes
    scope: subscription (per service principal, per region)
    metric: requests
    limit: 200
    burst: 200
    refill_per_second: 10
    timeFrame: second
    applies:
      - Azure CDN Management API (Microsoft.Cdn) — PUT, PATCH and action POST operations
  - name: Subscription deletes
    scope: subscription (per service principal, per region)
    metric: requests
    limit: 200
    burst: 200
    refill_per_second: 10
    timeFrame: second
    applies:
      - Azure CDN Management API (Microsoft.Cdn) — DELETE operations
  - name: Tenant reads
    scope: tenant (per region)
    metric: requests
    limit: 250
    burst: 250
    refill_per_second: 25
    timeFrame: second
  - name: Tenant writes
    scope: tenant (per region)
    metric: requests
    limit: 200
    burst: 200
    refill_per_second: 10
    timeFrame: second
  - name: Tenant deletes
    scope: tenant (per region)
    metric: requests
    limit: 200
    burst: 200
    refill_per_second: 10
    timeFrame: second
resource_provider_limits:
  microsoft_cdn:
    published: false
    note: >-
      The ARM throttling document lists resource-provider-specific limits for Microsoft.Storage,
      Microsoft.Network, Microsoft.Compute and Azure Resource Graph. Microsoft.Cdn publishes NO
      provider-specific limit, so the ARM subscription and tenant limits above are the only documented
      ceiling for Azure CDN management calls. Recorded as a checked absence.
policies:
  - name: Backoff
    description: >-
      Honour Retry-After on a 429. Requests sent before the retry value elapses are not processed and a
      new retry value is returned.
  - name: Pre-emptive backoff
    description: >-
      Read the x-ms-ratelimit-remaining-* header on every response and slow down before the bucket
      empties rather than after the 429.
  - name: SDK auto-retry
    description: >-
      The first-party Azure SDKs in packages/microsoft-azure-cdn-packages.yml implement retry policies;
      Microsoft directs clients to the Retry guidance for Azure services.
  - name: Per-region accounting
    description: >-
      Throttling is applied per region rather than per ARM instance, so the same subscription has an
      independent bucket in each region it addresses.
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com