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 Excel
providerId: microsoft-excel
created: '2026-05-04'
# Provenance stamped 2026-08-11: this artifact was written by the API Evangelist
# bulk sweep dated 2026-05-04, not harvested from the provider. See roadmap#35.
method: generated
modified: '2026-05-05'
reconciled: true
tags:
  - Rate Limiting
  - Spreadsheets
  - Microsoft Graph
  - Microsoft
description: The Microsoft Excel REST API is delivered through Microsoft Graph workbook endpoints and
  is throttled per (application, tenant) by the Excel service. Limits apply to all workbook requests regardless
  of the underlying Microsoft 365 plan. Returns 429 Too Many Requests with a Retry-After header.
sources:
  - https://learn.microsoft.com/en-us/graph/throttling-limits#excel-service-limits
  - https://learn.microsoft.com/en-us/graph/workbook-best-practice
headers:
  retryAfter: Retry-After
  requestId: request-id
  throttleScope: x-ms-throttle-scope
  throttleLimit: x-ms-throttle-limit-percentage
responseCodes:
  throttled: 429
  serviceUnavailable: 503
limits:
  - name: Excel — any request, per app per tenant
    scope: app/tenant
    metric: requests_per_10_seconds
    limit: 1500
    timeFrame: second
  - name: Excel — any request, per app across all tenants
    scope: application
    metric: requests_per_10_seconds
    limit: 5000
    timeFrame: second
  - name: Microsoft Graph global ceiling
    scope: application
    metric: requests_per_10_seconds
    limit: 130000
    timeFrame: second
    notes: Hard global ceiling per app across all Microsoft Graph services
policies:
  - name: Persist sessions
    description: Re-use the workbook-session-id header across calls; non-persisting sessions are limited
      to ~5 minutes and create unnecessary recompute.
  - name: Batch requests
    description: Use $batch on Microsoft Graph to combine up to 20 workbook calls per round-trip. Each
      batched call counts individually toward the limit but reduces network overhead.
  - name: Backoff Strategy
    description: Honour the Retry-After header on 429; exponential backoff with jitter otherwise.
  - name: Avoid recompute storms
    description: Set workbook calculation mode to manual for bulk writes, then trigger calculate at the
      end.
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com