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.
Prediction Markets — Polymarket & Kalshi, One Schema returns 9 documented output fields, including source, question, category, yesPrice and noPrice. Every field carries a declared type, a written description and an example value. 48 runs are recorded on Apify.
- 9
- Output fields
- 5
- Inputs
- 48
- Runs
- 2026-10-16
- Last run
01 — output
What it returns
Every field the extractor writes to its dataset, with its type, a written description and an example value.
| Field | Type | What it holds | Example |
|---|---|---|---|
| source | stringnull | Which upstream source produced this row. | official public API |
| question | stringnull | The question this record answers. | <question> |
| category | stringnull | Category this record belongs to, as classified upstream. | electronics |
| yesPrice | numbernull | Implied probability of the outcome, between 0 and 1. | 0 |
| noPrice | numbernull | Whether the listing has no published price. | 0 |
| volume | numbernull | Trading volume over the measured period. | 31157278261 |
| liquidity | numbernull | Liquidity measure as the source defines it. | 0 |
| status | stringnull | Outcome recorded for this row. | ok |
| url | stringnull | The URL this row describes. | https://example.com/pricing |
02 — sample
One record
Assembled from the example values declared on the schema above, not invented at render time.
{
"source": "official public API",
"question": "<question>",
"category": "electronics",
"yesPrice": 0,
"noPrice": 0,
"volume": 31157278261,
"liquidity": 0,
"status": "ok"
}03 — input
What you give it
| Input | Type | Description |
|---|---|---|
| sources | arrayoptional | Which venues to include: polymarket, kalshi, or both. |
| query | stringoptional | Keep only markets whose question, category or ticker contains this text (case-insensitive). Leave empty for all. |
| onlyOpen | booleanoptional | On: only markets currently trading. Off: also include closed/resolved markets. |
| minVolume | integeroptional | Drop markets with total volume below this. Leave empty to keep all. |
| maxItems | integeroptional | Hard limit on returned markets. Strictly enforced — you will never be charged for more than this. |
04 — run
Run Prediction Markets on your own input
It runs in the cloud on Apify. Nothing to install, and you are billed per result returned rather than per attempt.
05 — questions
Asked before running it
9 of 9 fields described
- What does Prediction Markets — Polymarket & Kalshi, One Schema return?
- It returns 9 documented output fields: source, question, category, yesPrice, noPrice, volume, liquidity, status and url. Each field declares its type, a description of what it holds, and an example value.
- What input does Prediction Markets — Polymarket & Kalshi, One Schema take?
- All 5 inputs are optional and ship with usable defaults, so it runs as-is. They are listed with their types below.
- Does Prediction Markets — Polymarket & Kalshi, One Schema need an API key or login?
- No. None of its inputs is a credential, and it reads only public data. Nothing to sign up for before the first run.
- How do I run Prediction Markets — Polymarket & Kalshi, One Schema?
- It runs on Apify. Start it from its listing with the inputs above, or call the Apify API with the Actor's ID. Results land in a dataset you can export as JSON, CSV or Excel, or read through the Apify API into your own pipeline.