---
title: "Simulate A Single Trade"
method: POST
path: "/simulate-trade"
tags: ["backtesting"]
---

# Simulate A Single Trade

`POST /simulate-trade`

## Request

- Base URL: `https://backtester.vast.tastyworks.com`
- URL: `https://backtester.vast.tastyworks.com/simulate-trade`
- Auth: none declared

Returns historical pricing for one trade without defining a full backtest. Supply an `underlying` and one or more `legs` (each leg uses tastytrade/OCC symbology), optionally bounded by `startTime`/`endTime`. The response is a time series of price points with the trade `effect` (debit or credit), `underlyingPrice`, and `delta`.

## Request body

- object
  - `underlying` string: Underlying symbol of the trade
  - `startTime` string, date-time: Optionally, start time of the trade in ISO 8601 format.
  - `endTime` string, date-time: Optionally, end time of the trade in ISO 8601 format.
  - `legs` object[]
    - `symbol` string: The leg symbol uses the tastytrade / OCC symbology convention - https://developer.tastytrade.com/api-overview/#tastytrade-symbology
    - `direction` 'long' | 'short'
    - `quantity` integer

## Response `200`

A time-ordered series of price points for the simulated trade.

- object[]
  - `dateTime` string, date-time
  - `price` string
  - `effect` 'debit' | 'credit'
  - `underlyingPrice` string
  - `delta` string

## Other responses

- `400`: The request body was malformed, for example an invalid leg `symbol` or `direction`.
- `401`: Unauthorized.
- `404`: No history is available for the requested underlying or time range.
- `429`: Request rate exceeded reasonable thresholds. Back off exponentially before retrying.

---

[API](https://skmtc.dev/tastytrade/apis/backtesting.md) - [All operations](https://skmtc.dev/tastytrade/apis/backtesting/llms.txt) - [OpenAPI document](https://skmtc.dev/tastytrade/apis/backtesting/revisions/482676159080?raw)