Strongest 15-minute lean
New here? How this works in 20 seconds
- Kalshi and Polymarket both let you bet on real-world questions, like “Will the Fed cut rates?”
- Sometimes they price the same question differently. Buy YES where it’s cheap and NO where it’s pricey, and exactly one of them pays out $1.
- If the two together cost less than $1 after fees, you keep the difference. That’s the gap. The rules on both sides have to match, or it’s not a sure thing.
Real money, real risk. Only use money you can afford to lose.
Close, but not there yet
These pass your rules filter but fall short on net gap or return.
Net gap is what’s left after both platforms’ taker fees, with both legs bought at the ask. The fee model here is a placeholder: Kalshi about 7% × price × (1 − price), and Polymarket’s category rates applied the same way (crypto 7%, economics, culture and weather 5%, politics, finance and tech 4%, geopolitics free), based on published schedules from mid-2026. Maker orders can cost less but may not fill. Check both platforms’ current fee pages before trading. Nothing here is financial advice.
Get pinged only for gaps you could actually trade.
Alerts skip stale quotes automatically and respect your size, rules and quiet-hours settings.
New alert
Recent alerts
Free to peek. Pay when speed matters.
Sized to the money at stake: a 3¢ gap on $500 is about $15, so Pro suits people trading hundreds per gap, and Trader suits people trading thousands.
Free
For checking whether gaps exist at all.
Pro
For traders sizing hundreds of dollars per gap.
Trader
For traders sizing $5k or more, and for bots.
Prices are a starting guess. Test them with real traders before launch.
Your watchlist
Open any gap in the Scanner and tap “Add to watchlist”. It stays here with live prices, saved on this device.
Track the trades you actually make.
Coming soon. Log both sides of a gap and see what you have locked in, and when it pays out.
Log a trade
Record the two legs you bought, the size, and the fees you paid.
Locked-in profit
See what is guaranteed, what is still open, and the days left until payout.
Watch for trouble
Get flagged if a market’s rules or prices change under a position you hold.
Export
Download your trades as a spreadsheet for taxes and records.
What the gaps tell you.
Coming soon. Parity records every price it sees, so this will show how gaps behave over time.
Gap history
How often each market opens a real gap, and how long it lasts.
Best times
When gaps tend to be widest, by hour and by day of the week.
Where gaps come from
Which categories and platform pairs produce the most real gaps.
Is it worth it?
Compare your yearly return against simply holding cash.
How Parity works
Plain-English answers. Prediction markets involve real money and real risk, and nothing here is financial advice.
What is a gap?
Kalshi and Polymarket let you bet on the same real-world question, like “Will the Fed cut rates?” Sometimes they price it differently. Buy YES on the cheaper one and NO on the other, and if both markets resolve the same way, exactly one side pays $1. If the two together cost less than $1 after fees, the difference is your profit. That difference is the gap.
Why the rules matter more than the price
Two markets can sound identical and still resolve differently: a different data source, cutoff time, or definition. If they resolve differently, both sides can lose. That is why Parity reads the rules and labels every pair Same rules, Small differences, or Big differences, and hides the risky ones by default.
What does “after fees” mean?
Both platforms charge fees when you buy. Parity estimates the fee on each side and subtracts it, so the “real gap” is what is left. The fee numbers are estimates: check each platform’s current fee page before you trade.
How much can I actually trade?
A price only applies to a limited number of contracts. Buy more and the price moves against you. Parity shows how many contracts are available on each side and sizes everything to the thinner one.
Yearly return and lock-up
Your money is tied up until the markets resolve. A 2% profit over 90 days is only about 8% a year. Parity shows the yearly equivalent so you can compare it with other places your money could sit.
Risks to know
- The two markets resolve differently, even when the titles match.
- Delays, voids, or disputes can tie up your money past the close date.
- Moving money between platforms costs time and sometimes fees or gas.
- Quotes can be stale. Check both order books before trading.
- Availability and rules depend on where you live. Check each platform yourself.
- Profits may be taxable.
Only use money you can afford to lose.
Quick glossary
- YES / NO
- The two sides of a market. One pays $1 when it resolves.
- Sell / buy
- The best price someone will pay you, and the best price you would pay.
- Contract
- One unit of a market. It pays $1 if you are right.
- Depth
- How many contracts are available at a price.
- Yearly return
- The profit scaled to a year, so short and long trades compare fairly.
Settings
Make Parity yours. Everything here is saved on this device.
Data
Using sample data.
Or a web address
Appearance
Accent Ember
Black hole background
Trading setup
This decides which Polymarket books and funding costs the scanner uses.
Notifications
Your alert rules live in the Alerts tab. Delivery to your phone needs the live backend.
Account
Parity is a prototype running on sample data. Nothing is connected to Kalshi or Polymarket yet.