API v4.0

Coin Metrics data is now available through a new, unified, simple to use API. At Coin Metrics, we continually invest in our technology and APIs to improve usability for our customers. API v4.0 highlights include:

  • Unification of the endpoints. v4.0 has a consistent and simple interface for all the endpoints and provides the data through two types of endpoints: catalog and timeseries
  • Improved speed for asset metrics timeseries endpoints for large requests
  • More meaningful error responses
  • Failover and graceful shutdown with zero client interruption during API updates
  • Ability to request multiple assets, metrics, and markets at once
  • Standardized nano timestamps in all responses and in the “timezone” query parameter


Contact us at if you would like to get access or learn more about the v4.0 API.

What’s new in the API v4.0


  • Consistent and simple structure with two types of endpoints: catalog & time series
  • Consistent naming for query parameters and response fields
  • “api_key” query parameter is the only authentication
  • Optional pretty print response formatting for all endpoints
  • Generalized asset metics frequencies so the same metrics can be retrieved using different frequencies and/or different EOD close times
  • Improved performance of catalog & time series endpoints
  • Typos handling: requests fail on unknown parameters or values
  • Meaningful error responses
  • Failover to another backend and graceful server shutdown during rolling updates


  • Two types of catalog endpoints:
    • /catalog for data available for specific api_key
    • /catalog-all for full catalog of all Coin Metrics data
  • Time ranges (min_time, max_time), height ranges, and hash ranges for each asset-metric pair time series (v2 shows this only on per asset basis)
  • Metrics, markets and indexes aren’t advertised via the catalog endpoint if we don’t have data for them in the database
  • New “community” flag for community metrics in the /catalog/assets endpoint
  • Flows metrics, which can change after manual review, are marked as “reviewable”
  • “reviewable” flag was added for metrics in the /catalog/metrics endpoint
  • Flows metrics now have “*-status” and “*-status-time” companion metrics
  • Improved markets discovery endpoint /catalog/markets with ability to filter results by asset, base, quote, type, exchange or symbol
  • New /catalog/indexes endpoint

Time series

  • Time series response format is Pandas friendly
  • Common query parameters among all time series endpoints
  • CSV output format for all asset metrics via “format” query parameter
  • Ability to request multiple assets, metrics or markets at once
  • Сonvenient and consistent paging of response – just open the “next_page_url” JSON field of responses to fetch the next page
  • Standardized nano timestamps in all responses and “timezone” query parameter
  • Consistent human-friendly and JavaScript-friendly number format – exponential/scientific notation is not used
  • Strict policy for gaps in the data; API doesn’t fill any gaps in the data
  • Strict policy for partially available metrics among requested ones:
    • missing metric name in the JSON response means that the metric is “not a supported metric”
      while some other requested metrics are supported.
    • null value of the metric means “no data in the database” while some other requested metrics have data.

Time series streaming

  • WebSocket streaming via the same domain (
  • No dropped messages in WebSocket endpoints due to another approach of handling slow clients
  • “warning” events in case of falling behind (60% send queue full) and “error” events before disconnection
  • PING frames for keeping WebSocket connection active to minimize chance of unexpected disconnections

MORE ON V4.0 VS. V2.0/3.0