--- {"title": "Kalshi vs Polymarket in 2026: Fees, Setup and Features", "description": "Kalshi and Polymarket compared on what each does and costs, and what to check before you pick one for trading predictions.", "url": "https://supakeeper.com/kalshi-vs-polymarket/", "date": "2026-10-11"} --- Kalshi and Polymarket compared on what each does and costs, and what to check before you pick one for trading predictions. Kalshi is a prediction market for trading the future [^1]. Polymarket describes itself as the world's largest prediction market [^2]. Model Odds ranks every Anthropic and OpenAI model family by its estimated chance of a release within 30 days [^3], and it is free, as is its API, with no account needed [^3]. Kalshi is subject to U.S. regulatory oversight by the CFTC [^1], while Polymarket US is operated by QCX LLC d/b/a Polymarket US, a CFTC-regulated Designated Contract Market [^2]. Trading is blocked in the United States on its main site, which directs people in the United States to its US site [^2]. Kalshi's sources given here state no dollar price and no fee, so its price is not published [^1]. Its page does say that members risk losing their cost to enter any transaction, including fees [^1]. Polymarket's sources given here state no price either, so its pricing is not published. Model Odds is free, and so is its API, with no account needed [^3]. | Option | Price | Account | Regulation | |---|---|---|---| | Kalshi | not published [^1] | not stated in the sources here | Subject to U.S. regulatory oversight by the CFTC [^1] | | Polymarket | not published [^2] | not stated in the sources here | US platform is a CFTC-regulated Designated Contract Market [^2]; international platform is not [^2] | | Model Odds | free, no account needed [^3] | not needed [^3] | web app that runs in the browser, needs JavaScript [^3] | ## The short answer Kalshi is a prediction market for trading the future [^1]. Polymarket describes itself as the world's largest prediction market [^2]. Model Odds ranks every Anthropic and OpenAI model family by its estimated chance of a release within 30 days [^3], and it is a web app that runs in the browser and needs JavaScript [^3]. On needs, Kalshi's page says it covers perpetual futures markets through Kalshi Pro [^1], and that it is subject to U.S. regulatory oversight by the CFTC [^1]. Polymarket's sources cover the world's largest prediction market [^2] and the fact that trading is blocked in the United States on its main site, which directs people in the United States to its US site [^2]. Model Odds' claims cover ranking each model family by release chance [^3], separate pages for Anthropic and OpenAI that list every past release [^3], and a public API [^3]. ## What Kalshi, Polymarket is built for Kalshi's own page calls it a prediction market for trading the future [^1], and says it is subject to U.S. regulatory oversight by the CFTC [^1]. It offers perpetual futures products through Kalshi Pro [^1] and runs an incentive program [^1]. Its pages also carry strict warnings: trading involves risk and may not be appropriate for all [^1], members risk losing their cost to enter any transaction, including fees [^1], and any trading decisions you make are solely your responsibility and at your own risk [^1]. Polymarket describes itself as the world's largest prediction market [^2], and operates globally through separate legal entities [^2]. Its United States operations are handled by QCX LLC d/b/a Polymarket US, a CFTC-regulated Designated Contract Market [^2]. The facts here give no more detail about its everyday function. ## What Model Odds is built for Model Odds is made by the team that publishes this site. It ranks every Anthropic and OpenAI model family by its estimated chance of a release within 30 days [^3]. Anthropic and OpenAI each get their own page that lists every past release [^3]. Each past launch the model uses has to be confirmed by an official post and an independent timeline, and it is listed with its date [^3]. The system runs three estimators side by side and publishes the spread between them as the error bar [^3]. The estimate is a renewal process fitted on the gaps between recent launches, and it takes into account how long the current wait has already lasted [^3]. Signals read automatically from company SDKs and docs, and from third-party model catalogues when two of them agree, can only raise the odds [^3]. The estimator can replay any past date without using data from after that date [^3]. An API serves per-line odds, the launch record and service health [^3]. ## Pricing and fees Kalshi's sources given here state no dollar price and no fee for trading, so its price is not published here [^1]. Its page does say that members risk losing their cost to enter any transaction, including fees [^1]. Kalshi offers perpetual futures markets through Kalshi Pro [^1] at no stated price, and its incentive program has no stated terms here [^1]. Polymarket's sources given here state no price and no fee, so its pricing is not published here. Model Odds is free, and so is its API, with no account needed [^3], and that is the only price its sources give. ## Setting it up and daily use Kalshi's sources here say nothing about installing the service or opening an account, so nothing is stated about setup. Day to day, Kalshi is a prediction market for trading the future [^1] and offers perpetual futures products through Kalshi Pro [^1]. Its sources say more about the risks than about day to day use: trading involves risk and may not be appropriate for all [^1], and members risk losing their cost to enter any transaction, including fees [^1]. Polymarket's sources state only that trading on its main site is blocked in the United States, which directs people in the United States to its US site [^2]. Model Odds is a website with a public API, so there is nothing to install [^3]. It is a web app that runs in the browser and needs JavaScript [^3]. The website and the API share one snapshot that is cached for up to five minutes [^3]. You can sign up with a confirmed email to get alerts, and every subscriber gets every company's drops at the same time [^3]. For Kalshi and Polymarket, the sources given here say nothing about how to set up an account or use the service day to day, so what to check instead appears below. ## Things to check before you choose Ask whether you can trade where you are. Trading on Polymarket's main site is blocked in the United States, which directs people in the United States to its US site [^2]. Kalshi's sources note it is subject to U.S. regulatory oversight by the CFTC [^1]. Ask what you are willing to lose. Kalshi says members risk losing their cost to enter any transaction, including fees [^1], and that trading involves risk and may not be appropriate for all [^1]. Ask what you actually want: the odds of a future model release, or a live prediction market. Model Odds covers Anthropic and OpenAI releases [^3], while Kalshi and Polymarket are prediction markets for the future [^1] [^2]. Ask what account and data handling each requires, since the facts here state nothing about it for any of the three. ## How to choose If you want the estimated chance of a release within 30 days for every Anthropic and OpenAI model family, Model Odds' claims describe that [^3]. If you want each past launch confirmed by an official post and an independent timeline and listed with its date, Model Odds' claims describe that [^3]. If you want to trade a prediction market for the future, Kalshi's page describes that [^1]. If you want a CFTC-regulated US market, Kalshi offers that [^1], as does Polymarket US [^2]. If you want the world’s largest prediction market, Polymarket’s page describes that [^2], but note that trading there is blocked in the United States [^2]. If you want a free tool with a public API and no account, Model Odds’ claims say that [^3] [^3]. ## Frequently asked questions ### Is Kalshi a regulated place to trade? Kalshi's own page says it is a prediction market for trading the future [^1], and that it is subject to U.S. regulatory oversight by the CFTC [^1]. Its page also warns that trading involves risk and may not be appropriate for all [^1], and that members risk losing their cost to enter any transaction, including fees [^1]. No fee or price is stated in the sources given here. ### Can you trade on Polymarket from the United States? Trading is blocked in the United States on Polymarket's main site, which directs people in the United States to its US site [^2]. The US site is operated by QCX LLC d/b/a Polymarket US, a CFTC-regulated Designated Contract Market [^2], while the international platform is not regulated by the CFTC and operates independently [^2]. The sources here give no price or fee for either. ### What does Model Odds tell a developer? Model Odds ranks every Anthropic and OpenAI model family by its estimated chance of a release within 30 days [^3]. Each company gets its own page that lists every past release [^3], and each past launch has to be confirmed by an official post and an independent timeline and is listed with its date [^3]. An API serves the odds, the launch record and service health [^3]. ### Is Model Odds free? Model Odds is free, and so is its API, with no account needed [^3]. It is a website with a public API, so there is nothing to install [^3]. It is a web app that runs in the browser and needs JavaScript [^3]. The website and the API share one snapshot that is cached for up to five minutes [^3]. ### Is Polymarket free to use? Polymarket describes itself as the world's largest prediction market [^2], and trading is blocked in the United States on its main site, which directs people in the United States to its US site [^2]. Its US arm is operated by QCX LLC d/b/a Polymarket US, a CFTC-regulated Designated Contract Market [^2], and the international platform is not regulated by the CFTC and operates independently [^2]. The sources given here state no price or fee. Model Odds is free, and so is its API, with no account needed. [^3] - [Visit Model Odds](/go/kalshi-vs-polymarket) ## Sources [^1]: Kalshi, kalshi.com, read 2026-10-08 (https://kalshi.com) [^2]: Polymarket, polymarket.com, read 2026-10-08 (https://polymarket.com) [^3]: Model Odds' own description of itself (the product of this site's publisher) (/go/kalshi-vs-polymarket)