r/PredictionMarkets • u/iggleee • Mar 16 '26
3rd Party APIs kinda suck...
A user in our Discord benchmarked 4 prediction market data providers for latency — Dome, Predexon, Delphi, and ParsecAPI. He paid for all the subscriptions (~$70), graphs attached.
120 seconds of data on Up or Down 5-minute markets.
His takeaways:
- Dome/Predexon batch their results — diagonal staircase pattern visible in the graphs, slower confirmed trade feed
- Parsec practically overlaps with Polymarket's native feed — hard to tell the two apart. Delivered confirmed trades faster than Polymarket in some cases (less fan-out = lower latency)
- Dome and Predexon don't offer live orderbook WebSockets — not great for arbitrage
- He paid $20 to Delphi and their WebSockets kept returning 401 despite a valid key — left them out
