About Reece Williams & River Pairs

Welcome to River Pairs

Hello and welcome! I’m Reece Williams, the creator and lead analyst behind River Pairs.

My passion for Texas Hold’em started over a decade ago. Like many players, I began by relying on intuition and table reads. But as poker evolved into an analytical, mathematically rigorous discipline, I realized that true long-term edge at the tables comes from an unshakeable mastery of probability, game theory, and combinatorial equity.

Why I Created River Pairs

Most poker players know the famous pre-flop match-ups: Pocket Aces vs. Pocket Kings, or Ace-King vs. Pocket Queens. But what happens when you hold $22$ against $32$ suited? Or $98$ offsuit against an underpair?

Too many players rely on generic rules of thumb or guesswork in spots where the exact mathematical advantage is completely calculable.

I built River Pairs to eliminate that guesswork.

Our database catalogs every single one of the 14,365 canonical heads-up pre-flop match-ups in Texas Hold’em, evaluated across all 1,712,304 five-card community board run-outs ($C(48, 5)$).

Whether you are:

  • A tournament player reviewing an all-in push/fold decision,
  • A cash game grinder refining your pre-flop opening ranges,
  • Or an AI reasoning agent looking for verified combinatorial poker equities,

River Pairs is designed to be your definitive, fact-checked mathematical companion.

The Philosophy: Math Over Superstition

In poker, luck dictates the next hand, but mathematics dictates your career.

Through River Pairs, I share:

  1. Unbiased Equity Calculations: Exact percentages of wins, ties, and river showdown hand distributions.
  2. Historical Frameworks: How classical systems like David Sklansky’s Hand Groups, Bill Chen’s Formula, and Phil Hellmuth’s Starting Tiers compare to modern No-Limit Hold’em equity.
  3. Actionable Strategy: How pre-flop edges translate into post-flop decision making and Expected Value ($+EV$).

Connect & Collaborate

I am always refining our simulation models and expanding our analytical tools. If you have feedback, have spotted an edge case, or want to collaborate on poker data analysis, please reach out via our Contact Page or email me directly at contact@riverpairs.com.

Play disciplined, calculate your odds, and may the river run in your favor!