Response Units

OnFinality uses Response Units for both API Billing and Rate Limiting.

Each API Response has a Response Unit weighting based on the computational power and network egress required to serve the response, resulting in fairer usage of shared node resources.

Response Unit weightings

The default response unit weighting is 1 across the majority of our networks, with the following exceptions:

• system_health has a Response Unit weighting of 0 across all networks. Many popular clients use system_health as a web sockets keep alive.

• Tracing methods such as state_traceBlock Trace API

• The following networks have higher Response Unit weightings for more intensive methods

  • Arbitrum

  • Base

  • BNB Chain

  • Celo

  • DFK Chain

  • Ethereum

  • Evmos

  • Fantom

  • Fuse

  • Harmony

  • Klaytn

  • Kava

  • OKT Chain

  • Optimism

  • Osmosis

  • Polygon

Why Responses instead of Requests?

With standard HTTPs JSON RPC (Remote Procedure Calls) one request receives one response. However, with web socket connections a single subscription can result in multiple responses per minute.

For example, subscribing to a chain’s head will receive a push response from the node every time there is a new block on the chain, usually every 6-12 seconds depending on the network. A single “subscription” request could go on to receive 600 responses over an hour.