Two prediction markets
Kalshi vs Polymarket
Both let you put money on the same game, and they get to their prices in different ways. Which means that several times a day they disagree about who is going to win. Here is what each one is, what each one costs you, and every disagreement between the two that Level has written down.
The two of them, side by side
Kalshi
- What it is
- A market where you buy contracts in an outcome. A contract costs somewhere between 1c and 99c and pays exactly $1 if that outcome happens, nothing if it does not.
- Who sets the price
- Nobody sets the price. It is whatever another trader will sell to you for right now, so it moves whenever someone changes their mind.
- What it costs you
- A trading fee that depends on the price. Put $100 into a contract at 50c and it costs $3.51; at 90c, where the outcome is closer to settled, it costs $0.70.
Polymarket
- What it is
- The same idea as Kalshi and the same $1 contract, on a different exchange with a different crowd trading it.
- Who sets the price
- Also set by whoever is willing to trade, which is why the same game can sit at a different price here than on Kalshi at the same moment.
- What it costs you
- A flat cut of what you put in, whatever the price: $2.00 on a $100 order.
Those fees are the ones Level subtracts before showing you a number, worked out by the same code. Nothing on this site quotes a fee it does not also charge against its own figures.
Why they end up disagreeing
Two separate crowds trading the same game in two separate places. Nothing forces the price on one to follow the price on the other, so when one side of a game gets bought heavily in one venue and not in the other, the two drift apart until somebody closes the distance.
When they drift far enough apart, backing one side on Kalshi and the other side on Polymarket pays back more than the two orders cost, whichever way the game goes. Far enough means after both fees and after the cost of your own order moving the price, which is most of the reason a gap that looks big turns out not to be one.
What we have recorded between these two
2,479
Gaps found
8.5%
Median gap
76.5%
Biggest gap
Seen so far in Ligue 1, EPL, La Liga, CS2, Bundesliga, MLS, Serie A, Dota 2, UCL, ATP, WTA, LoL, Valorant, NCAAF, MLB, NFL.
- Oct 19Marseille @ ToulouseKalshi + Polymarket23.5%
- Oct 19Chelsea @ Manchester UnitedPolymarket + Kalshi26.9%
- Oct 19Elche @ ValenciaKalshi + Polymarket31.9%
- Oct 19Bilbao @ Real SociedadKalshi + Polymarket30.3%
- Oct 19Getafe @ SevillaKalshi + Polymarket39.6%
- Oct 19ex-6666 vs Fire Flux EsportsPolymarket + Kalshi1.4%
- Oct 19Bremen @ HoffenheimKalshi + Polymarket23.2%
- Oct 19Salt Lake @ Saint LouisKalshi + Polymarket26.7%
- Oct 19ILLYRIANS vs WRAITH PCIFICPolymarket + Kalshi1.0%
- Oct 19Paris FC @ MonacoKalshi + Polymarket28.4%
- Oct 19FORZE Reload vs GenOneKalshi + Polymarket0.2%
- Oct 19M´gladbach @ PaderbornPolymarket + Kalshi21.9%
- Oct 19Genoa @ JuventusKalshi + Polymarket25.2%
- Oct 19Aston Villa @ FulhamKalshi + Polymarket26.7%
- Oct 19Liverpool @ ArsenalPolymarket + Kalshi28.4%
- Oct 19Torino @ ComoKalshi + Polymarket28.4%
- Oct 19Troyes @ Le MansPolymarket + Kalshi28.5%
- Oct 19Saint Sinners vs LilmixKalshi + Polymarket1.3%
- Oct 19Nemiga Gaming vs HULIGANIPolymarket + Kalshi2.0%
- Oct 19Manchester City @ BrightonKalshi + Polymarket22.1%
The 20 most recent of 2,479. Each percentage is what the quoted prices implied at the moment we saw them, after both fees and after the cost of your own order moving the price. Nobody placed these, and nothing already written down is ever recalculated. The whole record is on the log.
Before you go looking for one
You need an account at both, funded, before a gap shows up rather than after. Gaps close in minutes and a deposit does not clear in minutes, so an account with nothing in it is the same as no account when one appears.
And a gap is an estimate off public prices at a moment in time, not a guarantee. The price can move while you are placing the second order, and a pair where only one leg filled is an ordinary bet rather than a hedge. The walkthrough runs the whole thing end to end with real numbers, and today’s board is on the front page.
Other pairings
Kalshi vs DraftKingsKalshi vs FanDuelKalshi vs BetMGMKalshi vs BetRiversKalshi vs FanaticsKalshi vs CaesarsPolymarket vs DraftKingsPolymarket vs FanDuelPolymarket vs BetMGMPolymarket vs BetRiversPolymarket vs FanaticsPolymarket vs Caesars