Testnet — HIP-4 Prediction Markets

HIP-4 is currently testnet-only. These endpoints are not available on mainnet yet.

What is HIP-4?

HIP-4 introduces on-chain prediction markets (outcome trading) on Hyperliquid. Users can trade binary outcomes (Yes/No) on questions like “BTC above 66220 on Mar 29?” or multi-outcome questions like “What will Hypurr eat the most of in Feb 2026?”

Base URL

https://api.hypedexer.com/testnet

Key concepts

Concept	Description
Market (`#` coin)	A prediction market outcome (e.g. `#24371` = “BTC above 66220”)
Outcome Token (`@` coin)	The spot-tradeable token for an outcome (e.g. `@10` = CHUTORO)
Question	Groups related outcomes (e.g. question 1 → Akami, Otoro, Canned Tuna)
Settlement	Resolution of a market (settle_fraction: 0 = No, 1 = Yes)

Fee behavior

Prediction market fills (# coins) currently have fee = 0 on testnet — the SetOutcomeFeeScale governance action has not been activated.

Outcome token fills (@ coins) are charged normal spot fees (taker/maker rates). The fee_usdc field normalizes fees to USD equivalent.

Quick examples

curl -X 'GET' \
  'https://api.hypedexer.com/testnet/hip4/markets?question_id=1' \
  -H 'accept: application/json' \
  -H 'X-API-Key: YOUR_API_KEY'

curl -X 'GET' \
  'https://api.hypedexer.com/testnet/hip4/fills?user=0x079f56bfd27f71cbd278c27c7b121e7ef180a5be' \
  -H 'accept: application/json' \
  -H 'X-API-Key: YOUR_API_KEY'

curl -X 'GET' \
  'https://api.hypedexer.com/testnet/hip4/fees?user=0x1733d1945f023dfece04363d26f032ef069accdc' \
  -H 'accept: application/json' \
  -H 'X-API-Key: YOUR_API_KEY'
  

Overview

API documentation

Usage & limits

For Builders

Business

Testnet — HIP-4 Prediction Markets

What is HIP-4?

Base URL

Key concepts

Fee behavior

Quick examples

​What is HIP-4?

​Base URL

​Key concepts

​Fee behavior

​Quick examples

What is HIP-4?

Base URL

Key concepts

Fee behavior

Quick examples