R | Protocol (Rithmic API)

R | Protocol is Rithmic's application programming interface, the channel through which third-party software logs in to a Rithmic system, subscribes to market data and routes orders. Access to it is an entitlement distinct from using Rithmic's own R | Trader Pro platform.

Senzoukria · Glossary · Updated September 2026

How the API is structured

A client connects to a Rithmic gateway over a secure WebSocket address, asks for the list of systems that gateway serves, then logs in to one system with a username and password. From there it opens separate sessions to the plants it needs: market data for trades and depth, order routing for the account, history for past ticks or bars, and profit-and-loss. Each session is entitled on its own by the firm that issued the login.

Because the protocol is exposed to external software, Rithmic and the issuing firm control who may use it. Vendor applications are registered and named; an account can be permitted for one application and not for another, and a demo trial is not offered on the API at all.

  • Gateway: the access point, chosen by geography; some are colocation only.
  • System name: identifies the broker or prop firm environment on that gateway.
  • Plants: independent login sessions with their own heartbeats and permissions.

What an API login does not establish

  • That the account is subscribed to the instrument or exchange requested.
  • That depth is available, or to how many levels.
  • That historical ticks or bars exist for the dates requested; a permission-denied response on history is a broker entitlement, not a software setting.
  • That manual or automated order routing is permitted on this account stage.

In Senzoukria

The desktop implements R | Protocol directly, without a bridge, on the Rithmic Direct connection card. The card exposes the Gateway URL, which must start with wss://, an Access point list including a custom entry, and a Fetch live system list from gateway action that queries the gateway before you pick the System name. Credentials go to the operating-system keychain and should never be typed into a website form.

A notice on the same card explains that a free Rithmic demo cannot connect because Rithmic does not offer the R | Protocol API to demo accounts, and that R | Trader Pro accepting the same login does not change that. When the login succeeds and no tick arrives, the connection diagnostic lists the possible causes by frequency rather than showing an empty chart, since a closed market and a broken feed look identical on screen. The Rithmic attribution required by the provider is shown on the About page.

Common mistakes

  • Entering the R | Trader Pro gateway and expecting the API gateway to be the same.
  • Choosing a system name from memory instead of fetching the live list.
  • Reading a rejected history request as a bug in the chart.
  • Sharing an API login between two applications when the firm limits concurrent sessions.

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Frequently asked questions

Is R | Protocol the same as the Rithmic free trial?
No. The 14-day free demo gives live market data inside Rithmic's own platform, but the API is not offered to demo accounts, so third-party software cannot log in with those credentials whatever the system name. A broker- or prop-firm-issued account with API access is required.
Does using the API cost extra?
Fees are set by the issuing broker or prop firm and by the exchanges, not by the charting software. Some firms include API access in their account packages and others charge for it or restrict it by account stage; ask the firm in writing and keep the answer.

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