Pricing

from $20.00 / 1,000 contract pair priced across venues

Polymarket vs Kalshi Arbitrage — Same Question, Two Prices

Give it a question that trades on both Polymarket and Kalshi and get the price gap between them, after Kalshi's fee. Returns best bid and ask on each site, which site to buy on and sell on, the gap in cents per $1 contract. $0.02 per pair priced, suggestions included; refusals are free. Unofficial.

Pricing

from $20.00 / 1,000 contract pair priced across venues

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h ichi

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You can access the Polymarket vs Kalshi Arbitrage — Same Question, Two Prices programmatically from your own applications by using the Apify API. You can also choose the language preference from below. To use the Apify API, you’ll need an Apify account and your API token, found in API & Integrations in Apify Console.

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          "minLiquidityUsd": {
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Polymarket vs Kalshi Arbitrage — Spread After Fees OpenAPI definition

OpenAPI is a standard for designing and describing RESTful APIs, allowing developers to define API structure, endpoints, and data formats in a machine-readable way. It simplifies API development, integration, and documentation.

OpenAPI is effective when used with AI agents and GPTs by standardizing how these systems interact with various APIs, for reliable integrations and efficient communication.

By defining machine-readable API specifications, OpenAPI allows AI models like GPTs to understand and use varied data sources, improving accuracy. This accelerates development, reduces errors, and provides context-aware responses, making OpenAPI a core component for AI applications.

You can download the OpenAPI definitions for Polymarket vs Kalshi Arbitrage — Same Question, Two Prices from the options below:

OpenAPI.json

If you’d like to learn more about how OpenAPI powers GPTs, read our blog post.

You can also check out our other API clients:

Polymarket vs Kalshi Arbitrage — Same Question, Two Prices API in Python

Polymarket vs Kalshi Arbitrage — Same Question, Two Prices API in JavaScript

Polymarket vs Kalshi Arbitrage — Same Question, Two Prices API through CLI

Polymarket vs Kalshi Arbitrage — Same Question, Two Prices API

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Find the same question priced differently on Kalshi, Polymarket and PredictIt. Matches equivalent binary Yes/No markets across venues and reports the YES-price gap, the cheaper side, and whether that gap clears both venues bid/ask. Keyless, no browser. Pay per matched pair.

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Polymarket + Kalshi - Prediction Market Intelligence

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Unified live odds & implied probabilities from Polymarket and Kalshi in one feed. No key.

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Polymarket × Kalshi Arbitrage Scanner

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Scans Polymarket and Kalshi, matches equivalent binary markets and surfaces risk-free arbitrage opportunities and price divergences.

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Prediction Market Scanner — Polymarket vs Kalshi

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Search any topic and get live binary markets from Polymarket and Kalshi side by side — YES/NO prices, volume and links. Pairs the same yes/no question across both platforms and shows how their odds diverge.

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Polymarket & Kalshi Arbitrage Monitor

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Match public Polymarket and Kalshi binary contracts, compare outcome prices, and export confidence evidence with candidate cross-market spread calculations.

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Scrape Polymarket and Kalshi prediction markets in one run. Odds, prices, volume and close dates on one schema, as JSON or CSV.

Dominik

Kalshi Arbitrage Finder — Groups Priced Against $1

jpmarketdata/kalshi-odds-arbitrage

Pick Kalshi categories and get each event where at most one outcome can win, priced as a group: sell one contract of each. Returns money back from selling all, profit % before and after fees, and cash tied up. $0.02 per group priced — 17 in one 200-event run; unpriceable ones are free. Unofficial.

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Polymarket + Kalshi Arbitrage Finder

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Compare public Polymarket and Kalshi binary markets. Get ranked theoretical arbitrage opportunities with prices, opposing legs, liquidity, match confidence, and direct market links.

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Polymarket + Kalshi Arbitrage Finder

congism/polymarket-kalshi-arb-finder

Scans both Polymarket and Kalshi for matching binary prediction markets and identifies price discrepancies where buying YES on one platform and NO on the other guarantees a risk-free profit. Returns ranked opportunities with trade details and return %. Now covers PredictIt too - see our Arb Scanner.

Cong

719

Polymarket Kalshi Arbitrage Finder & Monitor

antndev/polymarket-kalshi-arbitrage-finder

Finds matched markets across Polymarket and Kalshi and computes fee-adjusted, order-book-depth-aware arbitrage edges. Monitor mode emits only new or changed opportunities and can push webhook alerts.