name: Nylas API Rate Limits
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: Nylas
providerId: nylas
created: '2026-05-04'
method: provider-published
authored_by: Nylas
modified: '2026-08-20'
source: https://developer.nylas.com/docs/dev-guide/platform/rate-limits/
best_practices: https://developer.nylas.com/docs/dev-guide/best-practices/rate-limits/
tags:
  - Calendar
  - Communication
  - Contacts
  - Email
  - Messaging
  - Scheduling
  - Rate Limiting
  - Quotas
  - Throttling
description: >-
  Published Nylas v3 rate limits, transcribed from
  developer.nylas.com/docs/dev-guide/platform/rate-limits/. Limits are per
  second and are scoped either per application or per grant, depending on the
  endpoint group. Nylas does not operate tier-based rate limits and does not
  apply a monthly request quota, so limits do not vary by plan. Nylas requests
  are additionally subject to the upstream provider's own limits, recorded under
  provider_limits below. This replaces a generated scaffold whose per-minute,
  per-tier values and monthly quotas did not correspond to any published Nylas
  limit.
headers:
  retryAfter: Retry-After
  providerRequestCount: Nylas-Provider-Request-Count
  gmailQuotaUsage: Nylas-Gmail-Quota-Usage
headerNotes: >-
  Nylas does not currently emit X-RateLimit-Limit, X-RateLimit-Remaining,
  X-RateLimit-Reset or RateLimit-Policy. Retry-After is returned when an
  upstream provider (Microsoft, EWS) throttles a request.
  Nylas-Provider-Request-Count reports how many upstream provider calls a single
  Nylas request consumed. Nylas-Gmail-Quota-Usage reports Google API quota
  consumed, on the Drafts, Messages, Threads, Folders and Attachments endpoints.
responseCodes:
  throttled: 429
limits:
  - name: Applications
    scope: application
    metric: requests_per_second
    limit: 50
    timeFrame: second
    applies:
      - Nylas API
    reference: https://developer.nylas.com/docs/reference/api/applications/
  - name: Authentication
    scope: application
    metric: requests_per_second
    limit: 50
    timeFrame: second
    applies:
      - Nylas API
    reference: https://developer.nylas.com/docs/reference/api/authentication-apis/
  - name: Connectors
    scope: application
    metric: requests_per_second
    limit: 50
    timeFrame: second
    applies:
      - Nylas API
    reference: https://developer.nylas.com/docs/reference/api/connectors-integrations/
  - name: Grants
    scope: application
    metric: requests_per_second
    limit: 50
    timeFrame: second
    applies:
      - Nylas API
    reference: https://developer.nylas.com/docs/reference/api/manage-grants/
  - name: Webhooks
    scope: application
    metric: requests_per_second
    limit: 50
    timeFrame: second
    applies:
      - Nylas API
    reference: https://developer.nylas.com/docs/reference/api/webhook-notifications/
  - name: Calendar
    scope: grant
    metric: requests_per_second
    limit: 200
    timeFrame: second
    applies:
      - Nylas API
    reference: https://developer.nylas.com/docs/reference/api/calendar/
  - name: Contacts
    scope: grant
    metric: requests_per_second
    limit: 200
    timeFrame: second
    applies:
      - Nylas API
    reference: https://developer.nylas.com/docs/reference/api/contacts/
  - name: Messages
    scope: grant
    metric: requests_per_second
    limit: 200
    timeFrame: second
    applies:
      - Nylas API
    reference: https://developer.nylas.com/docs/reference/api/messages/
  - name: Send (application/json)
    scope: grant
    metric: requests_per_second
    limit: 200
    timeFrame: second
    contentType: application/json
    applies:
      - Nylas API
    reference: https://developer.nylas.com/docs/reference/api/messages/send-message/
  - name: Send (multipart/form-data)
    scope: grant
    metric: requests_per_second
    limit: 10
    timeFrame: second
    contentType: multipart/form-data
    applies:
      - Nylas API
    reference: https://developer.nylas.com/docs/reference/api/messages/send-message/
provider_limits:
  - provider: Google
    notes: >-
      10,000 requests per minute per application and 600 per minute per user,
      calculated over a one-minute sliding window. Sending is capped at 2,000
      messages per day. Gmail API projects created on or after 2026-05-01 carry a
      per-project limit of 1,200,000 quota units per minute and a per-user limit
      of 6,000 quota units per minute.
  - provider: Microsoft
    notes: >-
      10,000 requests per 10-minute period, a maximum of 4 concurrent requests,
      and a maximum of 150 MB uploaded per 5-minute period. Sending is capped at
      30 messages per minute.
  - provider: EWS
    notes: >-
      Configured by the customer's own Exchange administrator, so Nylas cannot
      know the server's limits. Nylas returns Retry-After when the server
      throttles a request.
  - provider: iCloud
    notes: Apple caps sending at 1,000 messages per day.
policies:
  - name: Per-request provider fan-out
    description: >-
      A single Nylas request can make several calls to the upstream provider.
      Monitor Nylas-Provider-Request-Count, and Nylas-Gmail-Quota-Usage on
      Google, and space requests accordingly.
  - name: Threads endpoint cost
    description: >-
      Get all Threads makes a significant number of upstream provider calls per
      request. Use query parameters and a lower limit to reduce the number of
      results, which reduces the chance of hitting a provider limit.
  - name: Backoff strategy
    description: >-
      Retry with exponential backoff and jitter, honoring Retry-After when
      present. See the avoiding-rate-limits best practices guide.
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com