Prediction markets API

One prediction market's OHLC-style bars over a bounded window

The priced series for one market over a bounded window, in OHLC-style bars. A different question from the market's state: how the price moved, not what it is.

GET/api/external/prediction/prediction-market-bars/{id}

Get a free API key Try it in the API reference

What it returns

Per-bucket probability (0-1), volume and trade-count bars for one market, addressed by the id from GET /prediction/prediction-markets. Bounded by from/to (Unix seconds) and capped at 1000 bars per request.

Chains

This endpoint is not tied to a chain: it takes no chain in its request.

Request

Send your key in the x-dex-data-key header. Replace each <placeholder> with a real value.

curl -H "x-dex-data-key: $DEXDATA_API_KEY" \
  "https://api.dexdata.io/api/external/prediction/prediction-market-bars/<id>?resolution=min1&from=<from>&to=<to>"

Parameters
Parameter	Description
`resolution` query · string · required	The bucket width.`min1min5min15min30hour1hour4hour12day1week1`
`from` query · integer · required	Window start, Unix seconds (inclusive).
`to` query · integer · required	Window end, Unix seconds (inclusive). Per market, a window of ≤ 90 bars keeps the answer under 32 KB; a batch keeps markets × bars ≤ 80.
`id` path · string · required	A prediction-market id, e.g. "<marketAddress>:Polymarket:<exchangeAddress>:<networkId>" or "<slug>:Kalshi" — not a token mint or contract address, and not scoped to any chain this API otherwise supports.

Response fields

A JSON response. Every field is always present; null means the value could not be established, never zero.

Response fields of One prediction market's OHLC-style bars over a bounded window
Field	Type	Description
`marketId`	string \| null
`bars`	object[]
`bars[].t`	number \| null	Bucket open time, Unix seconds.
`bars[].volumeUsd`	number \| null	Volume across both outcomes in this bucket, USD.
`bars[].uniqueTraders`	number \| null
`bars[].trades`	number \| null
`bars[].allTimeVolumeUsd`	number \| null	Cumulative lifetime volume as of this bucket, USD.
`bars[].outcome0`	object \| null
`bars[].outcome0.trades`	number \| null
`bars[].outcome0.volumeUsd`	number \| null
`bars[].outcome0.priceUsd`	object \| null
`bars[].outcome0.priceUsd.o`	number \| null
`bars[].outcome0.priceUsd.h`	number \| null
`bars[].outcome0.priceUsd.l`	number \| null
`bars[].outcome0.priceUsd.c`	number \| null
`bars[].outcome1`	object \| null
`bars[].outcome1.trades`	number \| null
`bars[].outcome1.volumeUsd`	number \| null
`bars[].outcome1.priceUsd`	object \| null
`bars[].outcome1.priceUsd.o`	number \| null
`bars[].outcome1.priceUsd.h`	number \| null
`bars[].outcome1.priceUsd.l`	number \| null
`bars[].outcome1.priceUsd.c`	number \| null

Price per call

Every call: 141 credits

Charged only when the call succeeds. Prices as of 2026-10-30; the current ones are always in the API reference.

A prediction event's volume, liquidity and open interest over time
Same inputs: from, id, resolution, to.
One prediction-market trader's results bucketed over a window
Same inputs: from, id, resolution, to.
One prediction market's state and live outcome prices
The market's state right now, against how its price moved over a window.
Latest trades and redemptions on one prediction market
Every trade one by one, against price and volume already bucketed over time.
Many prediction markets' OHLC-style bars over a bounded window
The same answer for one market.
Many prediction markets' state and live outcome prices
Up to 25 prediction markets in one request: each one's lifecycle, windowed stats and the live price of each outcome.

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