# Prediction Markets — Polymarket & Kalshi, One Schema (`alaudinburki/prediction-markets-unified`) Actor

Live prices, volume and liquidity from Polymarket and Kalshi in one unified, CSV-ready dataset — so you can compare or arbitrage across both venues without writing two parsers. Free public APIs, no keys.

- **URL**: https://apify.com/alaudinburki/prediction-markets-unified.md
- **Developed by:** [alaudin burki](https://apify.com/alaudinburki) (community)
- **Categories:** News
- **Stats:** 2 total users, 1 monthly users, 100.0% runs succeeded, 0 bookmarks
- **User rating**: No ratings yet

## Pricing

from $2.50 / 1,000 results

This Actor is paid per event. You are not charged for the Apify platform usage, but only a fixed price for specific events.

Learn more: https://docs.apify.com/actors/running/actors-in-store.md#pay-per-event

## What's an Apify Actor?

Actors are web data automations that power AI and operations. They run on the Apify platform to scrape websites, process data, connect APIs, and automate workflows.
In Batch mode, an Actor accepts a well-defined JSON input, performs an action which can take anything from a few seconds to a few hours,
and optionally produces a well-defined JSON output, datasets with results, or files in key-value store.
In Standby mode, an Actor provides a web server which can be used as a website, API, or an MCP server.
Actors are written with capital "A".

## How to integrate an Actor?

If asked about integration, you help developers integrate Actors into their projects.
You adapt to their stack and deliver integrations that are safe, well-documented, and production-ready.
The best way to integrate Actors is as follows.

- **AI agents and MCP clients** — the [Apify MCP server](https://docs.apify.com/integrations/mcp.md) at `https://mcp.apify.com` (remote, streamable HTTP, OAuth on first use).
- **Agentic workflows and local Actor development** — [Agent Skills](https://apify.com/.well-known/agent-skills/index.json) with the [Apify CLI](https://docs.apify.com/cli/docs.md): `npm install -g apify-cli`, then `apify login`.
- **JavaScript/TypeScript projects** — the official [JS/TS client](https://docs.apify.com/api/client/js/docs.md): `npm install apify-client`.
- **Python projects** — the official [Python client](https://docs.apify.com/api/client/python/docs.md): `pip install apify-client`.
- **Any other language** — the [REST API](https://docs.apify.com/api/v2.md).

For usage examples, see the [API](#api) section below.

For more details, see Apify documentation as [Markdown index](https://docs.apify.com/llms.txt) and [Markdown full-text](https://docs.apify.com/llms-full.txt).

# README

## Prediction Markets — Polymarket & Kalshi, One Schema

Live prices, volume and liquidity from Polymarket and Kalshi in one unified, CSV-ready dataset — so you can compare or arbitrage across both venues without writing two parsers. Free public APIs, no keys.

Built reliability-first: **every row reports what was found and what was missing** — you never get a
silent blank, and a run summary tells you exactly what happened.

### What you get

| Field | Description |
|---|---|
| `source` | Source |
| `question` | Question |
| `category` | Category |
| `yesPrice` | Yes Price |
| `noPrice` | No Price |
| `volume` | Volume |
| `liquidity` | Liquidity |
| `status` | Status |
| `url` | Url |

### How to use it

1. Fill in the input (see the example below).
2. Run it once for a snapshot, or **schedule it** to keep the data fresh.
3. Export to CSV/JSON/Excel, or push straight to Google Sheets, Notion, Airtable, Zapier, Make, or n8n.

### Input

```json
{
  "sources": [
    "polymarket",
    "kalshi"
  ],
  "query": "",
  "onlyOpen": true,
  "maxItems": 1000
}
```

### Sample output

```json
[
{
  "source": "example",
  "question": "example",
  "category": "example",
  "yesPrice": 29.99,
  "noPrice": 29.99,
  "volume": 3.14,
  "liquidity": 3.14,
  "status": "ok",
  "url": "https://example.com/item/1"
}
]
```

### Typical uses

- **Cross-venue arbitrage** — same event on both venues, compare `yesPrice`; the unified
  schema makes the diff trivial.
- **AI trading agents** — a clean, stable feed of open markets with prices and volume.
- **Research / newsrooms** — snapshot what the crowd is pricing on a topic (`query`).

### Pricing

**$2.50 / 1,000 results** (`$0.0025` per result), plus a near-zero start fee. You are **never charged beyond your limit**, and blocked or
failed items are reported honestly — not billed as data.

### FAQ & limitations

- Both APIs are public and unauthenticated; if a venue's API is briefly down, this Actor
  returns the other venue's data and records the failure in `META.failedSources` — it never
  fakes a zero-row success.
- Polymarket doesn't expose open interest on this endpoint, so `openInterest` is null for
  Polymarket rows (populated for Kalshi).
- Prices are a snapshot at fetch time — schedule the run for a time series.
- **Integrations:** output works with Zapier, Make, n8n, and any webhook via Apify's integrations.
- **Formats:** results export as JSON, CSV, Excel, or HTML from the dataset.

### Related actors

- **Crypto Market Data**
- **Stock Market Data**
- **Prediction Markets**

# Actor input Schema

## `sources` (type: `array`):

Which venues to include: polymarket, kalshi, or both.

## `query` (type: `string`):

Keep only markets whose question, category or ticker contains this text (case-insensitive). Leave empty for all.

## `onlyOpen` (type: `boolean`):

On: only markets currently trading. Off: also include closed/resolved markets.

## `minVolume` (type: `integer`):

Drop markets with total volume below this. Leave empty to keep all.

## `maxItems` (type: `integer`):

Hard limit on returned markets. Strictly enforced — you will never be charged for more than this.

## Actor input object example

```json
{
  "sources": [
    "polymarket",
    "kalshi"
  ],
  "onlyOpen": true,
  "maxItems": 1000
}
```

# Actor output Schema

## `results` (type: `string`):

The dataset of results produced by this run.

# API

You can run this Actor programmatically using our API. Below are code examples in JavaScript, Python, and CLI, as well as the OpenAPI specification and MCP server setup.

## JavaScript example

```javascript
import { ApifyClient } from 'apify-client';

// Initialize the ApifyClient with your Apify API token
// Replace the '<YOUR_API_TOKEN>' with your token
const client = new ApifyClient({
    token: '<YOUR_API_TOKEN>',
});

// Prepare Actor input
const input = {
    "sources": [
        "polymarket",
        "kalshi"
    ],
    "query": "",
    "maxItems": 1000
};

// Run the Actor and wait for it to finish
const run = await client.actor("alaudinburki/prediction-markets-unified").call(input);

// Fetch and print Actor results from the run's dataset (if any)
console.log('Results from dataset');
console.log(`💾 Check your data here: https://console.apify.com/storage/datasets/${run.defaultDatasetId}`);
const { items } = await client.dataset(run.defaultDatasetId).listItems();
items.forEach((item) => {
    console.dir(item);
});

// 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/js/docs

```

## Python example

```python
from apify_client import ApifyClient

# Initialize the ApifyClient with your Apify API token
# Replace '<YOUR_API_TOKEN>' with your token.
client = ApifyClient("<YOUR_API_TOKEN>")

# Prepare the Actor input
run_input = {
    "sources": [
        "polymarket",
        "kalshi",
    ],
    "query": "",
    "maxItems": 1000,
}

# Run the Actor and wait for it to finish
run = client.actor("alaudinburki/prediction-markets-unified").call(run_input=run_input)

# Fetch and print Actor results from the run's dataset (if there are any)
print(f"💾 Check your data here: https://console.apify.com/storage/datasets/{run.default_dataset_id}")
for item in client.dataset(run.default_dataset_id).iterate_items():
    print(item)

# 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/python/docs/quick-start

```

## CLI example

```bash
echo '{
  "sources": [
    "polymarket",
    "kalshi"
  ],
  "query": "",
  "maxItems": 1000
}' |
apify call alaudinburki/prediction-markets-unified --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "type": "http",
            "url": "https://mcp.apify.com/?tools=fetch-actor-details,alaudinburki/prediction-markets-unified"
        }
    }
}

```

The hosted server signs you in with OAuth on first connect, so no API token belongs in this config. Clients without OAuth support can send an `Authorization: Bearer <APIFY_API_TOKEN>` header instead, using a token from API & Integrations in Apify Console (https://console.apify.com/settings/integrations).

## OpenAPI specification

Download the OpenAPI definition: https://api.apify.com/v2/actors/vlCqchXzF1M0DQJy8/builds/HJSbxhcsOPM5BWr75/openapi.json