Alpha Vantage limits and the Japanese stock gap

Description and use

The author found that Alpha Vantage’s free tier is limited to about five requests per minute and lacks Japanese stock data. He added sleeps between calls and switched to a Japan‑specific data source to ensure coverage and reliability.

Problem

The free tier of Alpha Vantage is tightly rate‑limited (~5 requests/min) and does not provide Japanese stock data, which is required for the author’s pipeline.

Outcome

The pipeline now respects Alpha Vantage’s rate limit and uses a dedicated Japanese data source, eliminating coverage gaps and ensuring reliable data ingestion.

Workflow

• 1. Measure Alpha Vantage request rate (≈5 req/min).
• 2. Add sleep between API calls to stay under the limit.
• 3. Verify coverage for required markets (US, Japan).
• 4. If coverage missing, select alternative source (Japan‑specific feed).
• 5. Apply same throttling discipline to the new source.
• 6. Build pipeline with coverage and rate‑limit checks as pre‑conditions.

Evidence

I measured roughly 5 requests per minute

Source

it doesn't cover Japanese stocks at all

Source

My fix was boring and effective: a sleep between requests

Source