Preview an order

curl --request POST \
  --url https://tradingapi.dev/v1/orders/preview \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "market": "BTC",
  "side": "buy",
  "type": "market",
  "value": "5000.00"
}
'

import requests

url = "https://tradingapi.dev/v1/orders/preview"

payload = {
    "market": "BTC",
    "side": "buy",
    "type": "market",
    "value": "5000.00"
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({market: 'BTC', side: 'buy', type: 'market', value: '5000.00'})
};

fetch('https://tradingapi.dev/v1/orders/preview', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

package main

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

func main() {

	url := "https://tradingapi.dev/v1/orders/preview"

	payload := strings.NewReader("{\n  \"market\": \"BTC\",\n  \"side\": \"buy\",\n  \"type\": \"market\",\n  \"value\": \"5000.00\"\n}")

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

	req.Header.Add("Authorization", "Bearer <token>")
	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))

}

{
  "object": "order_preview",
  "valid": true,
  "order": {
    "market": "BTC",
    "side": "buy",
    "type": "market",
    "requested_value": "5000.00",
    "reduce_only": false,
    "size": "0.0592",
    "price": null,
    "price_limit": "84430"
  },
  "estimate": {
    "average_fill_price": "84018.2",
    "price_impact_bps": "1.0",
    "value": "4973.88",
    "fee": "7.212126"
  },
  "position_after": {
    "direction": "long",
    "size": "0.0692",
    "entry_price": "83938.1",
    "value": "5814.06"
  },
  "account_after": {
    "available": "331.27"
  },
  "notes": [],
  "errors": []
}

Orders

Preview an order

Runs an order without placing it. The body is the same as for placing an order; client_order_id is optional and ignored. Nothing is recorded or sent.

The preview checks the request, your key’s limits and your balance, sizes the order as it would be sized now, and estimates the fill from the current order book. It returns the position and balance you would have afterwards.

A preview answers 200 whenever the body is a JSON object. When the order would be refused, valid is false and errors lists every reason at once, with the same error objects placing it would return.

POST

orders

preview

Preview an order

curl --request POST \
  --url https://tradingapi.dev/v1/orders/preview \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "market": "BTC",
  "side": "buy",
  "type": "market",
  "value": "5000.00"
}
'

import requests

url = "https://tradingapi.dev/v1/orders/preview"

payload = {
    "market": "BTC",
    "side": "buy",
    "type": "market",
    "value": "5000.00"
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({market: 'BTC', side: 'buy', type: 'market', value: '5000.00'})
};

fetch('https://tradingapi.dev/v1/orders/preview', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

package main

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

func main() {

	url := "https://tradingapi.dev/v1/orders/preview"

	payload := strings.NewReader("{\n  \"market\": \"BTC\",\n  \"side\": \"buy\",\n  \"type\": \"market\",\n  \"value\": \"5000.00\"\n}")

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

	req.Header.Add("Authorization", "Bearer <token>")
	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))

}

{
  "object": "order_preview",
  "valid": true,
  "order": {
    "market": "BTC",
    "side": "buy",
    "type": "market",
    "requested_value": "5000.00",
    "reduce_only": false,
    "size": "0.0592",
    "price": null,
    "price_limit": "84430"
  },
  "estimate": {
    "average_fill_price": "84018.2",
    "price_impact_bps": "1.0",
    "value": "4973.88",
    "fee": "7.212126"
  },
  "position_after": {
    "direction": "long",
    "size": "0.0692",
    "entry_price": "83938.1",
    "value": "5814.06"
  },
  "account_after": {
    "available": "331.27"
  },
  "notes": [],
  "errors": []
}

Authorizations

Authorization

string

header

required

An API key from the account page, sent as Authorization: Bearer tapi_….

Body

application/json

The same body as placing an order. client_order_id is optional and ignored.

market

any

required

side

any

required

type

any

required

value

any

required

client_order_id

any

price

any

reduce_only

any

metadata

any

Response

The preview.

object

string

required

Allowed value: "order_preview"

valid

boolean

required

Whether placing this order now would be accepted.

order

object | null

required

The order as it would be sized now.

Hide child attributes

order.market

string

order.side

enum<string>

Available options:

buy,

sell

order.type

enum<string>

market fills now at the best available prices, within 0.5% of the current price. limit fills now at your price or better; whatever cannot fill at once is canceled.

Available options:

market,

limit

order.requested_value

string | null

order.reduce_only

boolean

order.size

string

order.price

string | null

order.price_limit

string

estimate

object | null

required

The expected fill, from the current order book.

Hide child attributes

estimate.average_fill_price

string

estimate.price_impact_bps

string

How far the average fill is from the mid, in basis points.

estimate.value

string

estimate.fee

string

position_after

object | null

required

Your position if the order fills as estimated. null if it would close the position.

Hide child attributes

position_after.direction

enum<string>

Available options:

long,

short

position_after.size

string

position_after.entry_price

string

position_after.value

string

account_after

object | null

required

Hide child attributes

account_after.available

string

notes

object[]

required

Hide child attributes

notes.code

enum<string>

required

Available options:

size_rounded,

price_rounded,

position_flipped,

position_closed,

available_low,

partial_fill_likely,

trading_approval_expiring

notes.message

string

required

errors

object[]

required

Every reason the order would be refused, when valid is false.

Hide child attributes

errors.type

enum<string>

required

The kind of error. It determines the HTTP status.

Available options:

invalid_request,

authentication,

permission,

not_found,

conflict,

unprocessable,

rate_limited,

unavailable,

internal

errors.code

string

required

A stable identifier for the error. Branch on this. New codes may be added.

errors.message

string

required

What was wrong, with the values involved.

errors.param

string | null

required

The request field at fault, as a JSON path, or null.

errors.hint

string | null

required

One concrete way to fix the request.

errors.details

object

required

The numbers and values the message refers to, as fields.

errors.errors

array

required

Every field error, when code is invalid_fields. Empty otherwise.

errors.retryable

boolean

required

Whether the same request can succeed later, unchanged.

errors.doc_url

string<uri>

required

errors.retry_after

string<date-time>

When a retry can succeed, if known.

Overview

Markets

Orders

Positions

Account

Preview an order

Authorizations

Body

Response