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: Stooq
providerId: stooq
created: '2026-06-13'
modified: '2026-06-13'
reconciled: true
tags:
  - Fintech
  - Market Data
  - Rate Limiting
description: >-
  Stooq enforces a daily request quota per API key. The exact numeric limit is not publicly
  documented. When the quota is breached the API returns a plain-text or HTML error page with
  the message "Exceeded the daily hits limit" instead of CSV data; it does not return HTTP 429.
  Community reports indicate the quota is relatively low, so callers should implement request
  pacing, caching, and respect the daily cap. No per-minute burst limit is formally published.
sources:
  - https://stooq.com/db/h/
  - https://www.fundmanagersoftware.com/forum/viewtopic.php?f=7&t=6084
  - https://github.com/pydata/pandas-datareader/issues/1012
responseCodes:
  throttled: 200
  notes: >-
    Throttled responses return HTTP 200 with an error message body; clients must inspect the
    response body for the "Exceeded the daily hits limit" string rather than relying on the
    HTTP status code.
limits:
  - name: Free daily quota
    scope: api_key
    metric: requests_per_day
    limit: -1
    notes: Exact limit undisclosed; empirically reported as low. Error returned when exceeded.
policies:
  - name: Quota Error Detection
    description: >-
      Check response body for the string "Exceeded the daily hits limit". The HTTP status code
      will be 200, making standard rate-limit detection unreliable.
  - name: Request Pacing
    description: >-
      Space requests with a pause of at least 0.1 seconds between calls. pandas-datareader
      uses this default. For bulk retrieval, consider larger pauses to stay within the daily cap.
  - name: Caching
    description: >-
      Cache previously downloaded CSV data locally to avoid re-fetching the same date ranges,
      reducing quota consumption.
  - name: API Key Requirement
    description: >-
      As of early 2026 all /q/d/l/ requests must include an apikey query parameter. Obtain a
      key at https://stooq.com/q/d/?s=spy.us&get_apikey via an on-site CAPTCHA flow.
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com