# Interactive Brokers API error: orders request includes parameter with incorrect type

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This is the markdown version of https://openbrokerapi.com/errors/ibkr/web-api-400-parameter-incorrect-type, written from the same records as that page.

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The error, as text you can copy:

```
orders request includes parameter with incorrect type
```

- Kind: API error code
- HTTP status: 400
- API: [Interactive Brokers](https://openbrokerapi.com/brokers/ibkr)
- Status: verified. Source: [interactivebrokers.com](https://www.interactivebrokers.com/docs/web-api/v1/endpoints/orders/order-error-details), checked 2026-10-12.

## What does orders request includes parameter with incorrect type mean on the Interactive Brokers API?

Web API status 400 BadRequest, with the error message "orders request includes parameter with incorrect type" (the vendor's wording). Interactive Brokers lists it on its order error details page. The vendor's context: a field that needs a specific variable type received an invalid one.

## How do I fix orders request includes parameter with incorrect type?

The vendor refers to its Place Order reference for the supported types.

## More on the Interactive Brokers API

- [All Interactive Brokers API error codes](https://openbrokerapi.com/errors/ibkr)
- [Interactive Brokers API quickstart](https://openbrokerapi.com/brokers/ibkr/quickstart): From credentials to a first call on a demo account, step by step.
- [Interactive Brokers API error codes](https://openbrokerapi.com/errors/ibkr): 511 decoded, each with what it means, and the fix where the source gives one.
- [Interactive Brokers API endpoints](https://openbrokerapi.com/brokers/ibkr/endpoints): 23 documented, each with its method, path, parameters and source.
- [Interactive Brokers API page](https://openbrokerapi.com/brokers/ibkr): The full record: access, authentication, limits and the source for each.
- [Get your Interactive Brokers trade history into a spreadsheet](https://openbrokerapi.com/guides/ibkr-trade-history): Guide
- [IBKR API without TWS: headless IB Gateway options](https://openbrokerapi.com/guides/ibkr-headless-gateway): Guide
- [The three Interactive Brokers REST front doors compared](https://openbrokerapi.com/guides/ibkr-rest-front-doors): Guide
- [Interactive Brokers MCP servers, compared](https://openbrokerapi.com/guides/interactive-brokers-mcp-servers): Guide

## Licence and how to cite

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Cite as: Interactive Brokers API error: orders request includes parameter with incorrect type. Broker API Hub, https://openbrokerapi.com/errors/ibkr/web-api-400-parameter-incorrect-type, newest check 2026-10-12.

Where you rely on a single figure, cite the source and the checked date printed beside it as well. Where this page and a broker's own documentation differ, the documentation wins.