Events and markets

A market is one contract that pays $1 if its question resolves Yes; an event groups a venue’s markets the way people browse them. This page covers how the two are addressed, what an event and an outcome carry, how prices are stated, and the volume, spread, liquidity and book fields that travel with every market. You need it before reading any other response, since nearly all of them name a market.

Markets

A market is addressed by its venue and that venue’s own id: a ticker on Kalshi, a slug on Polymarket.

/v1/markets/kalshi/KXNFLTOTAL-26SEP17DETBUF-55
/v1/markets/polymarket/nfl-det-buf-2026-09-18-total-54pt5

curl "https://api.routeur.app/v1/markets/kalshi/KXNFLTOTAL-26SEP17DETBUF-55" \
  -H "X-API-Key: $ROUTEUR_API_KEY"

{
  "data": {
    "venue": "kalshi",
    "id": "KXNFLTOTAL-26SEP17DETBUF-55",
    "event_id": "KXNFLTOTAL-26SEP17DETBUF",
    "title": "Full Game: over 54.5 points scored?",
    "yes_label": "Over 54.5 points scored",
    "no_label": "Over 54.5 points scored",
    "category": "Sports",
    "strike": { "type": "greater", "floor": "109/2", "rules_template_hash": "f96c2ee0…" },
    "event_mutually_exclusive": false,
    "quote": { "yes_ask_usd": "0.52", "no_ask_usd": "0.49", "yes_bid_usd": "0.51", "no_bid_usd": "0.48", "observed_at": "2026-09-17T12:33:03.021417Z" },
    "relations": { "implies": 30, "implied_by": 16, "equivalent": 1, "contradicts": 0, "overlaps": 0, "cross_venue": 29 },
    "volume_24h_usd": "1076115.39",
    "volume_source": "venue",
    "total_volume_usd": "1085777.68",
    "open_interest_usd": "1067460.37",
    "spread_usd": "0.01",
    "yes_spread_usd": "0.01",
    "no_spread_usd": "0.01",
    "trades_24h": 1303,
    "liquidity": "deep",
    "book_spread_usd": "0.01",
    "book_yes_depth_5c_usd": "703799.64",
    "book_no_depth_5c_usd": "372781.50",
    "book_imbalance": "0.3075",
    "book_at": "2026-09-17T12:39:43.512632Z",
    "rules_hash": "e3f3063e…",
    "closes_at": "2026-09-20T00:15:00Z",
    "first_seen_at": "2026-09-14T17:31:31.849536Z",
    "rules": "If Detroit and Buffalo collectively score more than 54.5 points in the Detroit vs Buffalo Pro Football game originally scheduled for Sep 17, 2026, then the market resolves to Yes.…"
  }
}

Field	Type	Meaning
`venue`, `id`, `event_id`	string	The venue’s own identifiers.
`title`, `yes_label`, `no_label`	string	The question and its two sides, as the venue words them.
`category`	string	The venue’s own category. Events carry the shared category instead.
`strike`	object	The payoff condition as a range on the underlying quantity: `type`, exact rational `floor` and `cap`, and a `rules_template_hash` so markets compare only within one template.
`event_mutually_exclusive`	boolean	At most one market in the event can resolve Yes.
`game_starts_at`	timestamp	For games.
`quote`	object	The latest recorded asks and bids and when they were observed.
`relations`	object	How many markets this one implies, is implied by, equals, contradicts or overlaps, and how many of those are on the other venue. See Relations.
`rules_hash`, `rules`, `first_seen_at`, `closes_at`		The current contract version and its text. See Rules.

Size fields

Every object that names a market, in every response, carries the same size fields, because a price nobody can trade at is not a price:

Field	Type	Meaning
`volume_24h_usd`	decimal	Traded in the last 24 hours. The venue’s own figure where it publishes one; Kalshi counts contracts at their $1 face value, Polymarket reports USDC notional.
`volume_source`	`venue`, `trades`	Where that figure came from: the venue, or the notional of fills Routeur recorded when the venue gives none.
`total_volume_usd`	decimal	Traded over the market’s life, where the venue reports it.
`open_interest_usd`	decimal	Contracts currently held, at face value. Kalshi only.
`spread_usd`	decimal	The round trip: Yes ask plus No ask less the $1 a winner pays. Absent when a side has no ask.
`yes_spread_usd`, `no_spread_usd`	decimal	Ask less bid on each side, where the venue publishes a bid.
`trades_24h`	integer	Fills recorded in the last 24 hours.
`liquidity`	`deep`, `tradeable`, `thin`	The grade. See Liquidity.
`book_spread_usd`	decimal	From the recorded order book: best Yes ask less best Yes bid. Present for markets whose book is recorded.
`book_yes_depth_5c_usd`, `book_no_depth_5c_usd`	decimal	USD resting to buy each side within 5¢ of its best bid.
`book_imbalance`	decimal, −1 to 1	(Yes depth − No depth) / (Yes depth + No depth). Positive means more money resting on Yes.
`book_at`	timestamp	When the recorded book last changed. See Order books.

Lists that suggest something to act on leave thin markets out by default and rank the rest by the money behind them; min_volume_usd, max_spread_usd and include_thin change that wherever they apply.

Events

An event groups a venue’s markets: “Fed decision in October” holds one market per possible decision. When both venues list the same event and its outcomes are proven equivalent, GET /v1/events returns it once, with a twin and both venues’ asks on each outcome.

curl "https://api.routeur.app/v1/events/kalshi/KXFEDDECISION-26OCT" \
  -H "X-API-Key: $ROUTEUR_API_KEY"

{
  "data": {
    "venue": "kalshi",
    "id": "KXFEDDECISION-26OCT",
    "title": "Fed decision in Oct 2026?",
    "category": "Economics",
    "venues": ["kalshi"],
    "markets": 5,
    "mutually_exclusive": true,
    "closes_at": "2026-10-28T17:59:00Z",
    "volume_24h_usd": "618682.61",
    "trades_24h": 1958,
    "summary": "The market resolves based on the Federal Reserve's interest rate decision in October 2026.",
    "topics": ["federal reserve", "economics", "monetary policy", "interest rates", "fed funds rate"],
    "outcomes": [
      {
        "label": "Fed maintains rate",
        "venue": "kalshi",
        "market_id": "KXFEDDECISION-26OCT-H0",
        "title": "Will the Federal Reserve Hike rates by 0bps at their October 2026 meeting?",
        "chance": "0.5450",
        "change_24h": "-0.08",
        "prices": [
          { "venue": "kalshi", "market_id": "KXFEDDECISION-26OCT-H0", "yes_ask_usd": "0.55", "no_ask_usd": "0.46", "liquidity": "deep", "volume_24h_usd": "300469.46", "…": "…" }
        ],
        "volume_24h_usd": "300469.46",
        "liquidity": "deep",
        "…": "…"
      }
    ]
  },
  "graph_run": 74
}

Field	Type	Meaning
`venue`, `id`	string	The listing venue and its event id: an event ticker on Kalshi, a numeric id on Polymarket. A twin’s id returns the same event.
`category`	one of nine	The shared category: `Sports`, `Politics`, `Economics`, `Crypto`, `Culture`, `Tech & Science`, `Weather`, `World`, `Other`. `GET /v1/categories` lists them with counts.
`venues`	array	Every venue that lists the event.
`twin`	object	The same event on the other venue, when its outcomes are proven equivalent.
`markets`	integer	Markets in the event.
`mutually_exclusive`	boolean	At most one outcome can happen.
`starts_at`, `closes_at`	timestamp	When a game starts; when the event closes.
`volume_24h_usd`, `trades_24h`		Across every venue listing the event.
`summary`, `topics`		One line on what decides it, and the names it is about, from labeling. Each topic opens a topic page.
`outcomes`	array	Each backed by one market. Listings carry the three leading outcomes; `GET /v1/events/{venue}/{id}` carries every one.

Each outcome carries its label, the listing market’s venue, market_id and title, the implied chance, change_24h, an hourly sparkline of the last day’s Yes asks, the size fields above, and prices: the current asks on every venue with a proven-equivalent market, with best_venue naming the cheaper Yes when there is more than one.

Finding events

To	Use
Browse by category or volume	`GET /v1/events?category=Economics&sort=trending`
Browse what closes soonest	`GET /v1/events?sort=closing`
Only events on both venues	`GET /v1/events?cross_venue=true`
Find by meaning, in plain language	`GET /v1/search?q=fed+cut+october`
Browse by subject	`GET /v1/topics`, then `GET /v1/topics/{slug}`
More like this one	`GET /v1/events/{venue}/{id}/related`

GET /v1/events pages with limit (1 to 60, default 24) and offset. q matches event titles only; for plain-language search with filters, use /v1/search. See Search and topics.

Prices

Every price is an ask per contract that pays $1, as a decimal string in USD: what it costs to buy Yes or No right now. The implied chance of an outcome is the midpoint of its best Yes ask and one minus its best No ask across the venues that list it. Asks come from each venue’s recorded top of book on the last crawl; for resting size, read the order book, and for how prices moved, read History. Every graph-derived response names the graph_run it was read from; runs finish hourly.

Venues: what differs between Kalshi and Polymarket and how the API evens it out.
Liquidity: the grades and the floors.
Relations: what the relations counts mean.
Search and topics: finding events by what they are about.
Pagination: cursors and offsets.

Get started

Concepts

Agents & MCP

Webhooks

Reference

Events and markets

Markets

Size fields

Events

Finding events

Prices

Markets

Size fields

Events

Finding events

Prices

Related