Interactive Brokers vs MetaTrader 4 API
The same fields from the Interactive Brokers record and the MetaTrader 4 (MQL4) record, side by side. No winner is picked: which one suits you depends on what you are building.
Independent and unofficialNewest check
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.
What the two records show
Differences you can see in the records themselves. These are counts of what this site holds, not a verdict on either API.
- Interactive Brokers is recorded as a broker with an API of its own. MetaTrader 4 (MQL4) is a platform API, offered through the brokers that carry the platform.
- This site documents 23 endpoints for Interactive Brokers and no endpoints for MetaTrader 4 (MQL4). That counts what has been documented here, not what each API offers.
- This site has decoded 511 error codes for Interactive Brokers and 161 error codes for MetaTrader 4 (MQL4).
- The limits register holds 6 limit records for Interactive Brokers and no limit records for MetaTrader 4 (MQL4). Each limit record carries its own scope.
- The Interactive Brokers record holds a demo claim, verified at its source. The MetaTrader 4 (MQL4) record holds a demo claim, verified at its source. The wording of each is in the Demo row below.
- A quickstart is built here for Interactive Brokers only.
Interactive Brokers and MetaTrader 4 (MQL4), field by field
| Field | Interactive Brokers | MetaTrader 4 (MQL4) |
|---|---|---|
| Kind | Broker with its own API | Platform API, offered by many brokers |
| API family | TWS API (TCP socket), REST (Client Portal Web API), WebSocket | MQL4, WebRequest (HTTP from MQL4) |
| How you get access | No key: run TWS or IB Gateway (TWS API) or the Client Portal Gateway and log in via browser (Web API).IBKR TWS API documentation, the IB Gatewaychecked | Install the MT4 terminal from a broker and write Expert Advisors or scripts in MQL4.Install terminal (MT4 help)checked |
| Who can use it | Open, funded IBKR Pro account. The Web API supports only IBKR Pro accounts, and the TWS API lists a funded and opened IBKR Pro account among its requirements.IBKR Web API v1.0 documentation, requirements and limitationschecked | Real accounts can only be opened by brokerage companies that offer MT4.Opening of accounts (MT4 help)checked |
| Demo | Partial: paper trading accounts are supported and the Web API is logged in to with a separate paper username; demo accounts cannot subscribe to data.IBKR Web API documentation, using a paper accountchecked | Yes: demo accounts can be opened from within the terminal.Opening of accounts (MT4 help)checked |
| Authentication | TWS API: local socket to a TWS or IB Gateway the user has logged in to by hand. Web API: Client Portal Gateway with a browser login on the same machine; the Web API also lists OAuth 1.0a, OAuth 2.0 and SSO, and IBKR's older use cases page gives OAuth as the route for institutional clients.IBKR TWS API documentation, the IB Gatewaychecked | No API keys: code runs inside a terminal already logged in to a trading account.MQL4 Referencechecked |
| Streaming | TWS API is event driven over the socket. The Web API websocket is at /v1/api/ws (wss://localhost:5000/v1/api/ws through the gateway): the number of market data subscriptions depends on the account's market data lines, 100 by default, a market data stream ends after 15 minutes unless it is requested again, and at most 5 historical data requests run at once.IBKR Web API v1.0 documentation, websockets introductionchecked | In-terminal events only (new tick, timer, depth changes); no external streaming API.MQL4 Referencechecked |
| History depth | Bars of 30 seconds or less are not available beyond six months, and expired futures not beyond two years from expiry. IBKR's current TWS API documentation, read on 12 Oct 2026, counts three pacing violations for bars of 30 seconds or less: an identical historical data request within 15 seconds, six or more requests for the same contract, exchange and tick type within two seconds, and more than 60 requests in any ten minute period, with a BID_ASK request counted twice. The Web API endpoint /iserver/marketdata/history has its own published pacing of 10 requests a second or 50 a minute. Executions: since midnight by default, up to 7 days in TWS if its Trade Log setting is changed, and the current day only in IB Gateway.IBKR TWS API documentation, unavailable historical datachecked | Bars limited to the terminal's max bars in chart. Closed orders limited to what the Account History tab has loaded.MQL4 docs: CopyRateschecked |
| Limits |
| None recorded |
| Endpoints documented here | 23 | None yet |
| Error codes decoded here | 511 | 161 |
| Official documentation | interactivebrokers.com | docs.mql4.com |
Go deeper on each side
Interactive Brokers
- Interactive Brokers API page, the full record
- Interactive Brokers API quickstart, credentials to a first call
- Interactive Brokers API limits, in the table above
- Interactive Brokers API error codes, each with its fix
- Interactive Brokers API endpoints, each with its source
- Get your Interactive Brokers trade history into a spreadsheet
- IBKR API without TWS: headless IB Gateway options
- The three Interactive Brokers REST front doors compared
- Interactive Brokers MCP servers, compared
MetaTrader 4 (MQL4)
- MetaTrader 4 API page, the full record
- No MetaTrader 4 API quickstart is built here yet
- MetaTrader 4 API limits, in the table above: none recorded
- MetaTrader 4 API error codes, each with its fix
All comparisons. New to this? Getting started with API trading.