Statistics

Parameters

Name	In	Type	Required	Description
horse_id	path	string	yes	Opaque horse identifier.
by	query	string	no	A breakdown dimension: course, region, run_type, distance, going, surface, class, year, month, draw, field_size, layoff, sp_band, trainer, jockey, owner or sire. Omit for the overall block.
min_runs	query	integer	no	Drop breakdown rows with fewer runs than this. Defaults to 1.

Request

curl https://api.apihorseracing.com/v1/horses/hs_V8JGH6/stats \
  -H "X-API-Key: $AHR_KEY"

$ch = curl_init('https://api.apihorseracing.com/v1/horses/hs_V8JGH6/stats');
curl_setopt_array($ch, [
    CURLOPT_RETURNTRANSFER => true,
    CURLOPT_HTTPHEADER     => ['X-API-Key: ' . getenv('AHR_KEY')],
]);
$data = json_decode(curl_exec($ch), true)['data'];

const res = await fetch(
  'https://api.apihorseracing.com/v1/horses/hs_V8JGH6/stats',
  { headers: { 'X-API-Key': process.env.AHR_KEY } }
);
const { meta, data } = await res.json();

import os, requests

r = requests.get(
    "https://api.apihorseracing.com/v1/horses/hs_V8JGH6/stats",
    headers={"X-API-Key": os.environ["AHR_KEY"]},
).json()

Response

200 OK application/json harvested 8 days ago

{
    "meta": {
        "request_id": "e24d987d4b484093",
        "data_as_of": "2026-09-12T05:10:27+00:00",
        "plan": "analyst",
        "window": "2017 → upcoming",
        "count": 3
    },
    "data": {
        "horse_id": "hs_V8JGH6",
        "horse": "The Galloping Bear",
        "window": {
            "from": null,
            "to": null,
            "note": "The whole archive. Your plan sets no date limit."
        },
        "overall": {
            "runs": 17,
            "priced": 17,
            "first": 4,
            "second": 2,
            "third": 1,
            "fourth": 0,
            "win_pct": 0.2353,
            "top3_pct": 0.4118,
            "expected_wins": 2.41,
            "a_e": 1.657,
            "a_e_range": [
                0.033,
                3.281
            ],
            "a_e_beats_market": false,
            "significant": false,
            "low_sample": true,
            "pl_1pt": 7.56,
            "roi_pct": 44.47
        },
        "by": "course",
        "course": [
            {
                "course": "Chepstow",
                "runs": 3,
                "priced": 3,
                "first": 0,
                "second": 0,
                "third": 0,
                "fourth": 0,
                "win_pct": 0,
                "top3_pct": 0,
                "expected_wins": 0.36,
                "a_e": 0,
                "a_e_range": [
                    0,
                    5.487
                ],
                "a_e_beats_market": false,
                "significant": false,
                "low_sample": true,
                "pl_1pt": -3,
                "roi_pct": -100
            },
            {
                "course": "Newcastle",
                "runs": 2,
                "priced": 2,
                "first": 0,
                "second": 1,
                "third": 0,
                "fourth": 0,
                "win_pct": 0,
                "top3_pct": 0.5,
                "expected_wins": 0.15,
                "a_e": 0,
                "a_e_range": [
                    0,
                    12.923
                ],
                "a_e_beats_market": false,
                "significant": false,
                "low_sample": true,
                "pl_1pt": -2,
                "roi_pct": -100
            },
            "… 1 more"
        ]
    }
}

A real response from /v1/horses/hs_V8JGH6/stats?by=course&limit=3, captured by calling the live API rather than written by hand.

Response fields

Each field is described once and rendered on every endpoint that returns it, so the wording cannot drift between pages.

Field	Type	What it is
horse_id	string	Opaque horse identifier.
horse	string	Horse name.
window	string	How far back and forward that plan can read.
runs	integer	Rides in the slice, priced or not.
priced	integer	Rides carrying a starting price. A/E and the profit figures use these; runs is the wider count.
first	integer	Wins.
second	integer	Seconds. Positions are returned separately so you apply your own place terms.
third	integer	Thirds.
fourth	integer	Fourths.
win_pct	number	Wins over runs. The number everyone quotes and the one that tells you least.
top3_pct	number	First, second or third over runs. Not a place strike rate; place terms vary.
expected_wins	number	Wins the market implied, summed over the slice.
a_e	number	Actual wins over expected. Above 1.00 means winning more often than the prices said.
a_e_range	array	Ninety five percent interval on A/E. If it spans 1.00 the figure is not evidence of anything.
a_e_beats_market	boolean	True only where the whole interval sits above 1.00.
significant	boolean	Whether the interval excludes 1.00 in either direction.
low_sample	boolean	Fewer than five expected wins. Treat A/E as noise.
pl_1pt	number	One point on every runner, settled at starting price.
roi_pct	number	Level stakes return. Backing everything loses more than the book margin, because equal stakes overweight the longshots.
course	string	Course name.

Errors this endpoint returns

Code	Status	When
unauthorized	401	No key, or one we do not recognise. Check the header name and that the key has not been rotated from your account page.
upgrade_required	403	The endpoint returns computed statistics and your plan does not include them. The body names every plan that does reach it, so you never have to look it up.
not_found	404	The identifier is well formed but nothing has it. Distinct from invalid_id, which means the identifier itself is wrong.
invalid_id	422	The prefix does not match the kind of thing the path expects, or the identifier is malformed. A horse id passed where a race is wanted lands here rather than returning the wrong race.
invalid_param	422	A date that is not YYYY-MM-DD, a by= dimension we do not have, or a cursor that did not come from us. The message names the parameter.
rate_limited	429	Past your per-minute rate. Retry-After is set, and X-RateLimit-Remaining tells you where you stand on every successful response too.
server_error	500	Ours, not yours. Every response carries a request_id; quote it and we can find the exact request.

Run it live

A real request from your browser straight to api.apihorseracing.com with your own key. Nothing is proxied and nothing is logged by this page.

Your API key

Remembered in this browser so you do not paste it on every page.

horse_id

by optional

min_runs optional

What this is for

The standard statistics block for one horse: runs, wins, places, strike rate, A/E against the market, and level stakes profit, optionally split any of seventeen ways.

A/E is the number this tier exists for. It is actual wins against the wins the market implied, where the implied figure is normalised so that a field sums to one rather than to the book percentage. Above 1.00 means winning more often than the prices said; below means less. It is the only figure here that is not distorted by having run in easier or harder races, because the market has already priced that in.

Every A/E comes back with a range and a significant flag. An A/E of five over four runs is noise and used to look like the strongest signal in the payload. The interval is a Poisson one on the win count; significant is true only where it excludes 1.00, and low_sample is true under about thirty runs. <b>A single horse almost never reaches significance.</b> That is not a failing of the data, it is what a career of thirty runs can support.

Void and abandoned races are excluded, because a race with no winner contributed a full unit of expected wins and no actual win, dragging every A/E below 1.00.

Common uses

Finding the conditions a horse wants

by=going or by=distance over a long career. Read the range before you believe the headline: four runs on heavy proves nothing.

Checking a jockey booking

by=jockey shows who has actually got a tune out of this horse.

Feeding a model honestly

Take a_e and a_e_range together. Using the point estimate alone across thousands of horses is how a backtest finds an edge that is not there.

Notes

Level stakes assumes a one unit win bet at the returned starting price, with no commission and no place terms. It is a measure of the prices, not a strategy.

Available on