About
A free play-money forecasting league for forex and metals.
What it is
Brier Markets is a skill-based prediction market for currency pairs, gold, and Bitcoin. Sign up, get 10,000 virtual coins, and stake them on questions like "Will EUR/USD close above 1.10 this Friday?". Markets resolve automatically from broker price snapshots; the winning side splits the combined pool proportional to each bettor's stake.
How it works
- Browse open markets at /markets. Each one shows a YES / NO price between 1¢ and 99¢ — the implied probability based on how the crowd has split its money so far.
- Stake coins on YES or NO. Your stake drops into that side's pool; the implied price shifts as the two pools grow. There's no order book, no quote, no slippage — just two pools growing until the deadline.
- When the deadline passes, the market settles from a broker price snapshot. The entire combined pool flows to the winning side, allocated proportional to each winner's stake. The losing side keeps nothing — that's where the winners' profit comes from.
- Your Brier score, P&L, and rank update on the leaderboard. The best forecasters win bragging rights, not money — see /contest for the weekly sponsored prize.
Why this is legal
No real money is wagered, won, or lost on the markets themselves. Coins cannot be purchased, transferred, or redeemed. The site is in the same legal category as fantasy football scoring or chess Elo — a skill leaderboard. Available to users 18+ in jurisdictions where skill-based games are permitted.
What it is not
- Not investment advice.
- Not a brokerage.
- Not a regulated financial product.
- Not a price feed you should base trading decisions on. Prices are broker quotes posted hourly by a self-hosted MetaTrader 5 Expert Advisor — fine for settling skill markets, not for executing live trades.
The math
Markets are parimutuel — the same pool-betting model used in horse racing and jai alai. Every coin staked goes into one of two pools; at settlement the winning side's bettors split the combined pool. The operator never owes more than what was staked — conservation is exact.
- Implied YES probability:
no_pool / (yes_pool + no_pool). Defaults to 50¢ when both pools are empty. - Payout to a winner:
⌊stake × (yes_pool + no_pool) / winning_pool⌋. Floor-rounded so cumulative payouts never exceed the pool. - Single-bet cap:
max(1000, ⌊0.10 × total_pool⌋)— one bettor can't run away with the price. Split into multiple bets to size up further. - Void: if no broker snapshot is available within ±5 min of the deadline, the market voids and every position is refunded its full stake.
Forecast accuracy is scored with the standard Brier score: per-market contribution is (implied_yes_at_bet − actual)² where actual = 1 if YES won, 0 if NO won. Lower is better; perfect forecaster scores 0.
