Submit Order

curl --request POST \
  --url https://api.parlayx.com/v1/kalshi/orders \
  --header 'Content-Type: application/json' \
  --header 'Idempotency-Key: <idempotency-key>' \
  --header 'PX-Content-Sha256: <px-content-sha256>' \
  --header 'PX-Key-Id: <px-key-id>' \
  --header 'PX-Signature: <px-signature>' \
  --header 'PX-Timestamp: <px-timestamp>' \
  --data '
{
  "ticker": "KXPRES-2028",
  "side": "BID",
  "count": "10",
  "price": "0.38",
  "postOnly": true,
  "selfTradePrevention": "TAKER_AT_CROSS",
  "cancelOrderOnPause": true,
  "timeInForce": {
    "type": "GTC"
  },
  "clientOrderId": "order-1"
}
'

import requests

url = "https://api.parlayx.com/v1/kalshi/orders"

payload = {
    "ticker": "KXPRES-2028",
    "side": "BID",
    "count": "10",
    "price": "0.38",
    "postOnly": True,
    "selfTradePrevention": "TAKER_AT_CROSS",
    "cancelOrderOnPause": True,
    "timeInForce": { "type": "GTC" },
    "clientOrderId": "order-1"
}
headers = {
    "PX-Key-Id": "<px-key-id>",
    "PX-Timestamp": "<px-timestamp>",
    "PX-Signature": "<px-signature>",
    "PX-Content-Sha256": "<px-content-sha256>",
    "Idempotency-Key": "<idempotency-key>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {
    'PX-Key-Id': '<px-key-id>',
    'PX-Timestamp': '<px-timestamp>',
    'PX-Signature': '<px-signature>',
    'PX-Content-Sha256': '<px-content-sha256>',
    'Idempotency-Key': '<idempotency-key>',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    ticker: 'KXPRES-2028',
    side: 'BID',
    count: '10',
    price: '0.38',
    postOnly: true,
    selfTradePrevention: 'TAKER_AT_CROSS',
    cancelOrderOnPause: true,
    timeInForce: {type: 'GTC'},
    clientOrderId: 'order-1'
  })
};

fetch('https://api.parlayx.com/v1/kalshi/orders', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.parlayx.com/v1/kalshi/orders",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'ticker' => 'KXPRES-2028',
    'side' => 'BID',
    'count' => '10',
    'price' => '0.38',
    'postOnly' => true,
    'selfTradePrevention' => 'TAKER_AT_CROSS',
    'cancelOrderOnPause' => true,
    'timeInForce' => [
        'type' => 'GTC'
    ],
    'clientOrderId' => 'order-1'
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "Idempotency-Key: <idempotency-key>",
    "PX-Content-Sha256: <px-content-sha256>",
    "PX-Key-Id: <px-key-id>",
    "PX-Signature: <px-signature>",
    "PX-Timestamp: <px-timestamp>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.parlayx.com/v1/kalshi/orders"

	payload := strings.NewReader("{\n  \"ticker\": \"KXPRES-2028\",\n  \"side\": \"BID\",\n  \"count\": \"10\",\n  \"price\": \"0.38\",\n  \"postOnly\": true,\n  \"selfTradePrevention\": \"TAKER_AT_CROSS\",\n  \"cancelOrderOnPause\": true,\n  \"timeInForce\": {\n    \"type\": \"GTC\"\n  },\n  \"clientOrderId\": \"order-1\"\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("PX-Key-Id", "<px-key-id>")
	req.Header.Add("PX-Timestamp", "<px-timestamp>")
	req.Header.Add("PX-Signature", "<px-signature>")
	req.Header.Add("PX-Content-Sha256", "<px-content-sha256>")
	req.Header.Add("Idempotency-Key", "<idempotency-key>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.parlayx.com/v1/kalshi/orders")
  .header("PX-Key-Id", "<px-key-id>")
  .header("PX-Timestamp", "<px-timestamp>")
  .header("PX-Signature", "<px-signature>")
  .header("PX-Content-Sha256", "<px-content-sha256>")
  .header("Idempotency-Key", "<idempotency-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"ticker\": \"KXPRES-2028\",\n  \"side\": \"BID\",\n  \"count\": \"10\",\n  \"price\": \"0.38\",\n  \"postOnly\": true,\n  \"selfTradePrevention\": \"TAKER_AT_CROSS\",\n  \"cancelOrderOnPause\": true,\n  \"timeInForce\": {\n    \"type\": \"GTC\"\n  },\n  \"clientOrderId\": \"order-1\"\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.parlayx.com/v1/kalshi/orders")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["PX-Key-Id"] = '<px-key-id>'
request["PX-Timestamp"] = '<px-timestamp>'
request["PX-Signature"] = '<px-signature>'
request["PX-Content-Sha256"] = '<px-content-sha256>'
request["Idempotency-Key"] = '<idempotency-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"ticker\": \"KXPRES-2028\",\n  \"side\": \"BID\",\n  \"count\": \"10\",\n  \"price\": \"0.38\",\n  \"postOnly\": true,\n  \"selfTradePrevention\": \"TAKER_AT_CROSS\",\n  \"cancelOrderOnPause\": true,\n  \"timeInForce\": {\n    \"type\": \"GTC\"\n  },\n  \"clientOrderId\": \"order-1\"\n}"

response = http.request(request)
puts response.read_body

{
  "orderId": "3f8b2c9a-2d18-4f7e-9c2a-1b6e1f0c8a4d",
  "status": "OPEN",
  "filledCount": "4",
  "remainingCount": "6",
  "averagePrice": "0.384"
}

{
  "error": {
    "code": "INVALID_REQUEST",
    "message": "<string>",
    "orderId": "3c90c3cc-0d44-4b50-8888-8dd25736052a"
  }
}

{
  "error": {
    "code": "UNAUTHORIZED",
    "message": "<string>"
  }
}

{
  "error": {
    "code": "UNAUTHORIZED",
    "message": "<string>"
  }
}

{
  "error": {
    "code": "INVALID_REQUEST",
    "message": "<string>",
    "orderId": "3c90c3cc-0d44-4b50-8888-8dd25736052a"
  }
}

{
  "error": {
    "code": "IDEMPOTENCY_CONFLICT",
    "message": "Idempotency key was reused with a different request body"
  }
}

{
  "error": {
    "code": "UNAUTHORIZED",
    "message": "<string>"
  }
}

{
  "error": {
    "code": "INVALID_REQUEST",
    "message": "<string>",
    "orderId": "3c90c3cc-0d44-4b50-8888-8dd25736052a"
  }
}

{
  "error": {
    "code": "UNAUTHORIZED",
    "message": "<string>"
  }
}

POST

kalshi

orders

Submit Order

curl --request POST \
  --url https://api.parlayx.com/v1/kalshi/orders \
  --header 'Content-Type: application/json' \
  --header 'Idempotency-Key: <idempotency-key>' \
  --header 'PX-Content-Sha256: <px-content-sha256>' \
  --header 'PX-Key-Id: <px-key-id>' \
  --header 'PX-Signature: <px-signature>' \
  --header 'PX-Timestamp: <px-timestamp>' \
  --data '
{
  "ticker": "KXPRES-2028",
  "side": "BID",
  "count": "10",
  "price": "0.38",
  "postOnly": true,
  "selfTradePrevention": "TAKER_AT_CROSS",
  "cancelOrderOnPause": true,
  "timeInForce": {
    "type": "GTC"
  },
  "clientOrderId": "order-1"
}
'

import requests

url = "https://api.parlayx.com/v1/kalshi/orders"

payload = {
    "ticker": "KXPRES-2028",
    "side": "BID",
    "count": "10",
    "price": "0.38",
    "postOnly": True,
    "selfTradePrevention": "TAKER_AT_CROSS",
    "cancelOrderOnPause": True,
    "timeInForce": { "type": "GTC" },
    "clientOrderId": "order-1"
}
headers = {
    "PX-Key-Id": "<px-key-id>",
    "PX-Timestamp": "<px-timestamp>",
    "PX-Signature": "<px-signature>",
    "PX-Content-Sha256": "<px-content-sha256>",
    "Idempotency-Key": "<idempotency-key>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {
    'PX-Key-Id': '<px-key-id>',
    'PX-Timestamp': '<px-timestamp>',
    'PX-Signature': '<px-signature>',
    'PX-Content-Sha256': '<px-content-sha256>',
    'Idempotency-Key': '<idempotency-key>',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    ticker: 'KXPRES-2028',
    side: 'BID',
    count: '10',
    price: '0.38',
    postOnly: true,
    selfTradePrevention: 'TAKER_AT_CROSS',
    cancelOrderOnPause: true,
    timeInForce: {type: 'GTC'},
    clientOrderId: 'order-1'
  })
};

fetch('https://api.parlayx.com/v1/kalshi/orders', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.parlayx.com/v1/kalshi/orders",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'ticker' => 'KXPRES-2028',
    'side' => 'BID',
    'count' => '10',
    'price' => '0.38',
    'postOnly' => true,
    'selfTradePrevention' => 'TAKER_AT_CROSS',
    'cancelOrderOnPause' => true,
    'timeInForce' => [
        'type' => 'GTC'
    ],
    'clientOrderId' => 'order-1'
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "Idempotency-Key: <idempotency-key>",
    "PX-Content-Sha256: <px-content-sha256>",
    "PX-Key-Id: <px-key-id>",
    "PX-Signature: <px-signature>",
    "PX-Timestamp: <px-timestamp>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://api.parlayx.com/v1/kalshi/orders"

	payload := strings.NewReader("{\n  \"ticker\": \"KXPRES-2028\",\n  \"side\": \"BID\",\n  \"count\": \"10\",\n  \"price\": \"0.38\",\n  \"postOnly\": true,\n  \"selfTradePrevention\": \"TAKER_AT_CROSS\",\n  \"cancelOrderOnPause\": true,\n  \"timeInForce\": {\n    \"type\": \"GTC\"\n  },\n  \"clientOrderId\": \"order-1\"\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("PX-Key-Id", "<px-key-id>")
	req.Header.Add("PX-Timestamp", "<px-timestamp>")
	req.Header.Add("PX-Signature", "<px-signature>")
	req.Header.Add("PX-Content-Sha256", "<px-content-sha256>")
	req.Header.Add("Idempotency-Key", "<idempotency-key>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://api.parlayx.com/v1/kalshi/orders")
  .header("PX-Key-Id", "<px-key-id>")
  .header("PX-Timestamp", "<px-timestamp>")
  .header("PX-Signature", "<px-signature>")
  .header("PX-Content-Sha256", "<px-content-sha256>")
  .header("Idempotency-Key", "<idempotency-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"ticker\": \"KXPRES-2028\",\n  \"side\": \"BID\",\n  \"count\": \"10\",\n  \"price\": \"0.38\",\n  \"postOnly\": true,\n  \"selfTradePrevention\": \"TAKER_AT_CROSS\",\n  \"cancelOrderOnPause\": true,\n  \"timeInForce\": {\n    \"type\": \"GTC\"\n  },\n  \"clientOrderId\": \"order-1\"\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.parlayx.com/v1/kalshi/orders")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["PX-Key-Id"] = '<px-key-id>'
request["PX-Timestamp"] = '<px-timestamp>'
request["PX-Signature"] = '<px-signature>'
request["PX-Content-Sha256"] = '<px-content-sha256>'
request["Idempotency-Key"] = '<idempotency-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"ticker\": \"KXPRES-2028\",\n  \"side\": \"BID\",\n  \"count\": \"10\",\n  \"price\": \"0.38\",\n  \"postOnly\": true,\n  \"selfTradePrevention\": \"TAKER_AT_CROSS\",\n  \"cancelOrderOnPause\": true,\n  \"timeInForce\": {\n    \"type\": \"GTC\"\n  },\n  \"clientOrderId\": \"order-1\"\n}"

response = http.request(request)
puts response.read_body

{
  "orderId": "3f8b2c9a-2d18-4f7e-9c2a-1b6e1f0c8a4d",
  "status": "OPEN",
  "filledCount": "4",
  "remainingCount": "6",
  "averagePrice": "0.384"
}

{
  "error": {
    "code": "INVALID_REQUEST",
    "message": "<string>",
    "orderId": "3c90c3cc-0d44-4b50-8888-8dd25736052a"
  }
}

{
  "error": {
    "code": "UNAUTHORIZED",
    "message": "<string>"
  }
}

{
  "error": {
    "code": "UNAUTHORIZED",
    "message": "<string>"
  }
}

{
  "error": {
    "code": "INVALID_REQUEST",
    "message": "<string>",
    "orderId": "3c90c3cc-0d44-4b50-8888-8dd25736052a"
  }
}

{
  "error": {
    "code": "IDEMPOTENCY_CONFLICT",
    "message": "Idempotency key was reused with a different request body"
  }
}

{
  "error": {
    "code": "UNAUTHORIZED",
    "message": "<string>"
  }
}

{
  "error": {
    "code": "INVALID_REQUEST",
    "message": "<string>",
    "orderId": "3c90c3cc-0d44-4b50-8888-8dd25736052a"
  }
}

{
  "error": {
    "code": "UNAUTHORIZED",
    "message": "<string>"
  }
}

Headers

PX-Key-Id

string

required

The key id issued for your signing keypair.

PX-Timestamp

string

required

Unix seconds at signing, valid within 30 seconds of the server clock.

PX-Signature

string

required

Ed25519 signature of the request

PX-Content-Sha256

string

required

Hex SHA-256 of the request body, or the SHA-256 of the empty string when there is no body.

Idempotency-Key

string

required

Idempotency key for this request. Re-sending the same key with the same body returns the original result and creates no duplicate; re-sending it with a different body is rejected with 422.

Minimum string length: 1

Example:

"2f1a8c4e-0b3d-4a9c-8e7f-1a2b3c4d5e6f"

Body

application/json

ticker

string

required

Kalshi market ticker identifying the market to trade.

Minimum string length: 1

Example:

"KXPRES-2028"

side

enum<string>

required

Order direction on the market's YES book.

Side	Meaning
`BID`	Buy YES contracts, profiting if the market resolves YES.
`ASK`	Sell YES contracts, profiting if the market resolves NO.

Selling YES is the same order as buying NO, so ASK covers both.

Available options:

BID,

ASK

Example:

"BID"

count

string

required

Order size in contracts, as a decimal string. Contracts trade in steps of 0.01.

Example:

"10"

price

string

required

Limit price per contract in dollars, as a decimal string on the market's YES book. A price off that market's tick grid is rejected.

Example:

"0.38"

postOnly

boolean

Reject the order if it would cross the book instead of resting as a maker.

selfTradePrevention

enum<string>

Which order is cancelled when this order would trade against your own resting order.

Policy	Meaning
`TAKER_AT_CROSS`	Cancels this order, leaving the resting one on the book.
`MAKER`	Cancels the resting order and lets this one keep matching.

Defaults to TAKER_AT_CROSS.

Available options:

TAKER_AT_CROSS,

MAKER

Example:

"TAKER_AT_CROSS"

cancelOrderOnPause

boolean

Cancel the order if the exchange pauses trading, instead of leaving it resting.

timeInForce

GoodTillCancelled · object

Execution policy; defaults to GTC.

GoodTillCancelled
ImmediateOrCancel
FillOrKill
GoodTillDate

Show child attributes

clientOrderId

string

Your own identifier for this order, returned unchanged on every read of it. Each value may be used only once.

Required string length: 1 - 64

Example:

"order-1"

Response

Order accepted; status is the order's recorded state, and acceptance alone does not mean it is resting or filled

orderId

string<uuid>

required

Issued order id.

Example:

"3f8b2c9a-2d18-4f7e-9c2a-1b6e1f0c8a4d"

status

enum<string>

required

Order lifecycle status.

Status	Meaning
`PENDING`	Accepted, not yet sent to the venue.
`SUBMITTED`	At the venue, outcome not yet known. Either not yet acknowledged, or an immediate-or-cancel order acknowledged but not yet settled.
`OPEN`	Resting on the venue, and cancellable.
`FILLED`	Fully filled.
`CANCELLED` / `REJECTED`	Terminal.

Available options:

PENDING,

SUBMITTED,

OPEN,

FILLED,

CANCELLED,

REJECTED

Example:

"OPEN"

filledCount

string | null

required

Contracts filled immediately when the venue acknowledged the order, or null if unreported.

Example:

"4"

remainingCount

string | null

required

Contracts still resting when the venue acknowledged the order, or null if unreported.

Example:

"6"

averagePrice

string | null

required

Average price per contract in dollars on the market's YES book, of the contracts filled at acknowledgement, or null if none filled.

Example:

"0.384"

Authentication

Discovery

Polymarket

Kalshi

ProphetX

Limitless

Submit Order

Headers

Body

Response