John Harris

About John

John has followed prediction markets since the Intrade era. He has traded on Kalshi, Polymarket and PrizePicks and writes about market accuracy, regulation, and platform comparisons. Background in financial analysis.

Credentials and Experience

• 8 years in financial markets, prediction market trader since 2015
• Active prediction market trader on Kalshi, Polymarket, and PrizePicks
• Tracks accuracy, regulation, and platform comparisons across the prediction market category
• Has followed the prediction market category continuously since the Intrade era

Editorial Approach

John writes platform reviews, comparisons, and analysis pieces for PredictSites. Every piece goes through fact-checking by our research editor before publication. We do not accept payment for ranking placement and we maintain editorial independence from the affiliate relationships that fund the site.

Read about our broader editorial process and methodology on our about page.