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Interactive Brokers API POST /iserver/account/{accountId}/orders/whatif

POST/iserver/account/{accountId}/orders/whatifversion v1Orders

Projects the effect of an order before you send it: cost, change to equity, initial and maintenance margin, and position.

Risk warning: CFDs and spread bets are complex instruments and come with a high risk of losing money rapidly due to leverage. You can lose money on these products, and each provider publishes its own loss figure under FCA rules. You should consider whether you understand how they work and whether you can afford to take the high risk of losing your money. Automated and API trading can amplify losses through bugs, connectivity failures and runaway orders.

Independent and unofficialinteractivebrokers.comchecked

Nothing is sent to the market. IBKR lists amount, equity, initial, maintenance and position as objects; the keys inside them in our mock are invented, so check them against a real preview.

Parameters

NameInTypeDescription
accountIdrequiredpathstringYour IBKR account ID. The code reads it from the IBKR_ACCOUNT_ID environment variable. Never type it into this site.
ordersbodyarrayArray of order ticket objects. IBKR: only one order ticket may be submitted per request, unless constructing a bracket.

Authentication headers

NameTypeDescription
AuthorizationstringOAuth only; the Gateway sends none. On the OAuth host this is the SSO bearer token IBKR's reference lists for this call. With the Client Portal Gateway on your own computer the browser login holds the session. Placeholder only.

Request

Written from the method, path and parameters recorded on this page. No demo host is recorded as a plain address for this API, so the samples read the base address from an environment variable. Not executed against a live or demo account. Credentials are read from environment variables on your own machine and are never entered on this site. The request builder writes these same snippets, from the same record.

This call takes a request body. The record marks no body field as required, so the samples send an empty JSON object with a Content-Type of application/json (in Python, passing json= sets that header). Add the fields the call needs from the parameters above before the request can succeed.

Python
# Set IBKR_BASE_URL, IBKR_ACCOUNT_ID as environment variables first. Never paste real values into code.
# No demo host is recorded as a plain address for this API, so the base address is read from IBKR_BASE_URL.
# Optional and not shown: headers Authorization; body fields orders.
import os
import requests

BASE_URL = os.environ["IBKR_BASE_URL"]
headers = {}
body = {}
resp = requests.post(BASE_URL + "/iserver/account/" + os.environ["IBKR_ACCOUNT_ID"] + "/orders/whatif", headers=headers, json=body, timeout=10)
resp.raise_for_status()
print(resp.json())
JavaScript
// Set IBKR_BASE_URL, IBKR_ACCOUNT_ID as environment variables first. Never paste real values into code.
// No demo host is recorded as a plain address for this API, so the base address is read from IBKR_BASE_URL.
// Optional and not shown: headers Authorization; body fields orders.
// Run as a module, for example a .mjs file, on a Node version that has fetch built in.
const BASE_URL = process.env.IBKR_BASE_URL;
const res = await fetch(BASE_URL + "/iserver/account/" + process.env.IBKR_ACCOUNT_ID + "/orders/whatif", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
  },
  body: JSON.stringify({}),
});
if (!res.ok) throw new Error(`HTTP ${res.status}`);
console.log(await res.json());
curl
# Set IBKR_BASE_URL, IBKR_ACCOUNT_ID as environment variables first. Never paste real values into code.
# No demo host is recorded as a plain address for this API, so the base address is read from IBKR_BASE_URL.
# Optional and not shown: headers Authorization; body fields orders.
curl -X POST "$IBKR_BASE_URL/iserver/account/$IBKR_ACCOUNT_ID/orders/whatif" \
  -H "Content-Type: application/json" \
  -d '{}'

Response

A mock response. The values are invented, so check field names against the official reference.

{
  "_mock": true,
  "amount": {
    "amount": "1,850.00 USD",
    "commission": "1.00 USD",
    "total": "1,851.00 USD"
  },
  "equity": {
    "current": "10,000",
    "change": "-1",
    "after": "9,999"
  },
  "initial": {
    "current": "2,000",
    "change": "0",
    "after": "2,000"
  },
  "maintenance": {
    "current": "1,500",
    "change": "0",
    "after": "1,500"
  },
  "position": {
    "current": "10",
    "change": "-10",
    "after": "0"
  },
  "warn": null,
  "error": null
}

Response schema, HTTP 200

Every field this site's OpenAPI file for Interactive Brokers declares for this response.

FieldTypeDescription
amountobjectNot recorded
equityobjectNot recorded
initialobjectNot recorded
maintenanceobjectNot recorded
positionobjectNot recorded
warnstring, nullableNot recorded
errorstring, nullableNot recorded

interactivebrokers.comchecked

Limits that apply at Interactive Brokers

LimitValueScopeSource
Global requests a second (Web API)10Per authenticated username, that is per Web API sessionibkrcampus.comchecked corroborated by interactivebrokers.com/docs/web-api/trading/usage-and-availability/pacing-limitations
Historical market data requestsEither 10 req/s or 50 req/minute, as the page words itGET /iserver/marketdata/history onlyinteractivebrokers.comchecked corroborated by ibkrcampus.com/campus/ibkr-api-page/webapi-doc/
Market data snapshot requests a second10GET /iserver/marketdata/snapshot onlyinteractivebrokers.comchecked corroborated by ibkrcampus.com/campus/ibkr-api-page/webapi-doc/
Order and trade list requests1 req/5 sGET /iserver/orders and GET /iserver/trades, each counted on its owninteractivebrokers.comchecked corroborated by ibkrcampus.com/campus/ibkr-api-page/webapi-doc/
Session validation requests a minute1GET /sso/validate onlyinteractivebrokers.comchecked corroborated by ibkrcampus.com/campus/ibkr-api-page/webapi-doc/
Session keep alive requests a second1GET /tickle onlyinteractivebrokers.comchecked corroborated by ibkrcampus.com/campus/ibkr-api-page/webapi-doc/

Interactive Brokers API errors you may meet

All Interactive Brokers API error codes, including 505 more not listed here.