Official venue APIsAPIfree
SX Bet API: what it exposes, how it authenticates, where it stops
Last checked 2026-09-08
SX Bet is a peer-to-peer sports prediction market with an open order book, settled in USDC from a proxy wallet the exchange deploys for you. The V3 API at https://api.sx.bet documents every route, a Toronto testnet mirrors mainnet, and a docs MCP server is offered for coding assistants.
It is for sports traders who want to quote both sides programmatically and want to rehearse on testnet first.
What the API exposes
Public without a key: sports, leagues, teams, active fixtures, live scores, search, GET /markets/active, /markets/find, /markets/popular, the order book snapshot and the anonymized public trade tape. Keyed: best odds, your orders, positions, trades, fills and balances, plus proxy wallet deployment and funding routes.
V3 collapses maker and taker into one endpoint: POST /orders-v3 with timeInForce GTC to rest or IOC and FOK to execute. Odds are implied probability times 10^20, stakes are USDC base units (6 decimals), and an odds ladder with a default step of 0.125% is enforced.
Realtime is WebSocket only at wss://realtime.sx.bet/connection/websocket on Centrifugo v6.9.1. Public channels include orderbook_v3 per market or event, best_odds_v3:global, recent_trades_v3:global, markets:global, main_line:global, fixtures and parlay requests; account channels carry your orders, trades and fills.
Authentication and rate limits
Three tiers: none for market data, an x-sx-api-key header for private reads and WebSocket subscriptions, and key plus an EOA signature for placing orders and account actions. Keys are generated on the account page and shown once; testnet keys do not work on mainnet.
Per-key limits per 60 seconds: POST /orders-v3 5,500, GET /orders-v3 1,200, DELETE /orders-v3 10,000, cancel by event 120, cancel all 60, heartbeat 600, fills, positions and trades 300 each, balance 300, fees 120.
Pricing and access
No API fee and no application: sign up at sx.bet, export the private key from the assets page, generate a key, deploy and fund the proxy wallet. Testnet USDC comes from support chat, and the testnet base URL is https://api.toronto.sx.bet.
Fees are per account, not global. GET /user/fees-v3 returns makerPayoutFee, takerPayoutFee, makerParlayPayoutFee, takerParlayPayoutFee (charged on profit of winning bets at settlement) and refundFee (charged at fill on capital-efficiency refunds). A null rate means nothing is charged. Bridging out via Glide carries a 0.33% withdrawal fee; the Arbitrum native bridge is the documented alternative for large withdrawals.
Where it falls short
Sports only, and V2 integrations must migrate: the key header, order signing and endpoint shape all changed in V3.
A deployed and funded proxy wallet is a hard prerequisite before the first order, and your fee rates are only knowable by calling the API.
No official SDK is listed; the quickstart uses requests, eth-account and centrifuge clients directly.
Who should use it
Market makers and arbitrageurs in sports who want a testnet, high write limits and a maker-side fee structure that can be zero.
Developers who need politics or macro markets will not find them here.
Questions about SX Bet API
Does SX Bet have a testnet?
Yes. The Toronto testnet mirrors mainnet at https://api.toronto.sx.bet with its own accounts, API keys and support-issued testnet USDC.
Do I need an API key to read SX Bet markets?
No. Markets, order book snapshots and the public trade tape are open. A key is needed for best odds, your own data and WebSocket subscriptions; orders also need a signature.
What are the SX Bet API rate limits?
Per key per 60 seconds: 5,500 order placements, 10,000 cancels, 1,200 order reads, 300 reads each for fills, positions and trades.
What are SX Bet fees?
Set per account and returned by GET /user/fees-v3: payout fees on winning profit at settlement (maker and taker, single and parlay) plus a refund fee at fill time.
Official APIs for building. One book for trading.
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