Free Prediction Market Tracker Spreadsheet
Log every contract, every fee and every exit, then see whether the prices you paid were actually good.
Prediction market apps show you positions. They do not show you, across every venue you use, what you really made after fees or whether your 30-cent contracts win more than 30% of the time. This tracker does both.
What is in the prediction market tracker
Summary
Positions logged, money tied up in open positions, realized profit and ROI, total fees, contract-weighted win rate vs average price paid, a Brier score, and a calibration table by price band.
Positions
Venue, market, side, contracts, entry price in cents and fees. Mark it Sold, Settled - won or Settled - lost when it closes, and cost basis, proceeds, profit and ROI calculate.
| Side | Contracts | Entry | Fees | Status | Exit | Profit |
|---|---|---|---|---|---|---|
| Yes | 100 | 30¢ | $1.00 | Settled - won | 100¢ | $69.00 |
| No | 50 | 70¢ | $0.00 | Settled - lost | 0¢ | -$35.00 |
| Yes | 200 | 40¢ | $0.00 | Sold | 55¢ | $28.00 |
| Yes | 10 | 20¢ | $0.00 | Open |
How to use it
A contract price is a probability
A contract that pays $1 if the event happens and trades at 30 cents implies a 30% chance. That makes prediction markets easy to grade: over many settled contracts, the ones you bought at 30 cents should win more than 30% of the time if you are finding value. The tracker records the implied probability at entry on every row so you can check.
Track fees or your profit is fiction
Venues charge in different ways: a fee per contract, a share of expected profit, a spread, or a withdrawal fee. Small fees on cheap contracts add up fast. The tracker takes entry and exit fees on every position and nets them out of cost basis and proceeds, so realized profit is what actually reached your account.
Selling early vs holding to settlement
Many positions never settle because you sell first. Mark those Sold and enter your exit price; profit counts, but the position is left out of the calibration table, since it never resolved and says nothing about whether your probability was right.
Calibration and the Brier score
The Summary tab buckets settled positions by entry price (1 to 20 cents, 21 to 40, and so on) and compares the average price you paid with how often those contracts won. The Brier score rolls that into one number: 0 is perfect, and paying 50 cents on everything scores 0.25. Both need a few hundred settled positions before they mean much.
One sheet across every venue
Use the Venue column to tag where each position lives. Because everything is in cents and dollars, positions from different apps sit side by side, and you can filter by venue to see where your results actually come from.
Convert prices to sportsbook odds
Thinking in American odds? A 62-cent contract is about -163. Run any price through the free prediction market calculator to see the odds and implied probability, then compare it with the same outcome on BettorEdge, where sports outcomes trade between people at community odds.
Better prices make every row better.
Bet against people, not the house, on BettorEdge. Sign up for a shot at up to $100. No deposit needed.
Get new templates and tools by email
We send the occasional new sheet, calculator and betting market explainer. Free, no spam.
Frequently asked questions
How do you calculate profit on a prediction market contract?+
Profit = contracts x exit price - contracts x entry price - fees. A 100-contract position bought at 30 cents with a $1 fee costs $31. If it settles Yes it pays $100, a $69 profit. The tracker does this for every row.
What does the implied probability at entry mean?+
It is the price you paid divided by the $1 payout. A 30-cent contract implies a 30% chance. Comparing that with how often your contracts actually win tells you whether you are buying underpriced or overpriced outcomes.
What is a Brier score?+
A measure of forecast accuracy: the average of (probability - outcome) squared across settled forecasts, where the outcome is 1 or 0. Lower is better. 0 is perfect and always forecasting 50% scores 0.25.
Can I track No positions?+
Yes. Enter the price you paid for the No contract and mark Settled - won if No was the result. Everything is measured from the side you hold.
Does it work for any prediction market app?+
Yes. The Venue column is a dropdown with common venues plus Other, and you can type any name. All math runs on contracts, cents and dollars, which every venue uses.
Is the prediction market tracker free?+
Yes. The download needs no email and no account. The newsletter signup below it is optional.