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HomeOverviewTradingRisk & LiquidationsParadex ChainEcosystemREST APIWebSocket APIAgentic AI HubRelease Notes
HomeOverviewTradingRisk & LiquidationsParadex ChainEcosystemREST APIWebSocket APIAgentic AI HubRelease Notes
  • Getting Started
    • Overview
    • Privacy Perps
    • Trading Fees
    • Trader Profiles
    • Retail Price Improvement
    • FastFills
    • TradFi Markets
  • Spot Trading
    • Supported Order Types
    • Quoting & Settlement
    • Non-USDC Balances & Collateral
    • Naming Convention
  • Dated Options
    • Overview
    • Expiries and listing schedule
    • Mark price
    • Greeks
    • Margin requirements
    • FAQ
  • Orders
    • Placing Orders
    • Order Instructions
    • VWAP Price Protection for Market Orders
    • Price Impact and Slippage
    • How to Change Max Slippage
    • Margin Calculator
    • Self Trade Prevention
    • Receive Window
  • Instruments Guide
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On this page
  • Overview
  • How RPI Works
  • Matching Rules
  • Order Behavior and Visibility
  • Limitations and Restrictions
  • Placing an RPI Order

Retail Price Improvement

Better pricing for retail traders with selective order visibility
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Overview

Retail Price Improvement (RPI) is a specialized order type that provides better pricing and execution opportunities for retail traders while protecting market makers from toxic flow. It achieves this through selective order visibility - orders are visible in the UI but hidden from API access.

How RPI Works

Visible on UI

Enabling retail users to access improved pricing and better execution opportunities

Hidden from API

Protecting market makers from potentially harmful trading patterns

Matching Rules

RPI orders follow specific matching rules to ensure fair and efficient trading:

  1. Retail-Only Matching: RPI orders will only match with orders placed by non-algorithmic users and do not execute against orders submitted via API.

  2. Post-Only Requirement: All RPI orders must be Post-Only, meaning they will only provide liquidity and never take liquidity.

  3. Execution Priority: RPI orders have the lowest execution priority, regardless of when they’re placed. They will only be filled after all non-RPI orders at the same price level have been executed.

Order Behavior and Visibility

  1. Order Persistence: Accepted and resting RPI orders remain active until canceled by the user, even if they are no longer at the best bid or offer (BBO).

  2. Cross Book Behavior: The orderbook visible in the UI may appear crossed due to RPI orders that are not matching with API orders. The crossed section of the book is visible and highlighted in the UI. However, the API orderbook remains uncrossed as it does not contain any RPI orders.

Limitations and Restrictions

  • Orders must be placed through the API interface
  • RPI orders cannot be placed in combination with other special order types
  • Minimum order size requirements may apply

Placing an RPI Order

1

Use the New Order endpoint

Make a request to the New Order endpoint

2

Set RPI instruction

Set instruction="RPI" in your order parameters