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: PubNub
providerId: pubnub
created: '2026-05-08'
# Provenance stamped 2026-08-11: this artifact was written by the API Evangelist
# bulk sweep dated 2026-05-08, not harvested from the provider. See roadmap#35.
method: generated
modified: '2026-05-08'
reconciled: false
tags:
  - Realtime
  - Rate Limiting
description: >-
  PubNub does not publish per-second rate limits in the same way as competitors because billing
  is by MAU and transactions are unlimited within tier. Soft fair-use protections apply per
  publish key (typically 100 publishes per second per channel). Functions invocations are
  capped per second per function. Throttled responses return HTTP 429.
notes: PubNub explicitly markets unlimited messaging within plan; soft caps below.
sources:
  - https://www.pubnub.com/pricing/
  - https://www.pubnub.com/docs/general/api-reference
responseCodes:
  throttled: 429
limits:
  - name: Per-channel publish (soft)
    scope: channel
    metric: messages_per_second
    limit: 100
    notes: Soft fair-use; shard across channels for higher rates.
  - name: Functions per-instance
    scope: function
    metric: invocations_per_second
    limit: 100
    notes: Per-deployed-function fair-use.
  - name: MAU monthly cap
    scope: account
    metric: mau_per_month
    limit: -1
    notes: Per plan tier; see plans file.
policies:
  - name: Backoff Strategy
    description: Honor 429 Retry-After and apply exponential backoff with jitter.
  - name: Channel sharding
    description: Use channel groups and sharded channels to scale beyond per-channel publish soft limit.
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com