{"id":193950,"date":"2023-07-25T11:11:49","date_gmt":"2023-07-25T15:11:49","guid":{"rendered":"https:\/\/ibkrcampus.com\/?post_type=trading-lessons&p=193950"},"modified":"2025-10-03T13:16:04","modified_gmt":"2025-10-03T17:16:04","slug":"requesting-market-data","status":"publish","type":"trading-lessons","link":"https:\/\/www.interactivebrokers.com\/campus\/trading-lessons\/requesting-market-data\/","title":{"rendered":"Requesting Market Data"},"content":{"rendered":"\n

Hello, and welcome to this lesson on requesting market data in the Interactive Brokers Client Portal API. In this lesson, we will be discussing how to find the snapshot fields, how to request live market data snapshots, and how to request historical market data.<\/p>\n\n\n\n

Finding Market Data Fields<\/h4>\n\n\n\n

Let\u2019s begin by first looking at the Interactive Brokers endpoints documentation page. If we scroll down, we will eventually find our iserver\/marketdata\/snapshot endpoint that we will be working with today. If we click on the banner, we will expand the snapshot section to reveal more information on the endpoint. The reason to point out this section is that we can find what data values we want to work with. Under the \u2018Responses\u2019 portion, I can see here where it shows \u2018Model\u2019. If we click that, we should find a new grey box.<\/p>\n\n\n\n

I can click that right-pointed arrow to expand things, I will see a massive list of all available field values to use with the snapshot endpoint. Some of the most popular values are 31, 55, 84, and 86. As we can see by looking through this page, I will retrieve my last price, symbol, bid, and ask values respectively. There are many more values here that we encourage you to explore, but this will give us a great example to get started. With our fields found, we can start taking a closer look at the actual request.<\/p>\n\n\n\n

Requesting Market Data<\/h4>\n\n\n\n

Jumping back to VS Code, I will create a new program with my typical framework, and a method named marketSnapshot(). I will create my endpoint for my market data request and set to \u201ciserver\/marketdata\/snapshot\u201d. The snapshot endpoint utilizes a GET request, so now we can start building the parameters list.<\/p>\n\n\n\n

We can first create a conid variable, and set it equal to \u201cconids=265598\u201d. Some viewers may have picked up the fact that we stated \u201cconids\u201d instead of just \u201cconid\u201d. That is because this endpoint allows for multiple contract requests at once. You will just need to use a comma to separate each contract ID. Let\u2019s do that by including IBM, or 8314.<\/p>\n\n\n\n

With our contracts set, I will move on to our fields variable. I will set this variable equal to \u201cfields=31,55,84,86\u201d based on what we found before. That is all we need in order to get started with our requests. I will create a params variable, and concatenate my parameters. After that I can create my full url with the request_url set to \u201c\u201d.join([base_url, endpoint, \u201c?\u201d, params]).<\/p>\n\n\n\n

Again, I can create a market_req variable and create a new GET request. I can use my json.dumps() method from before to help with readability. And finally, we will print both variables to see our response status and body. So if we make a few requests, we should see all of our fields returned.<\/p>\n\n\n\n

Discussing the return<\/h4>\n\n\n\n

I would like to take a moment to discuss how data is requested and returned. The first request will typically only display the coindex, and the conid. This is just to signify that you have requested data for the given contract. You can think of it as instantiating the market data stream. Often times for stocks, you can make another follow up request right away, and receive data. However, it\u2019s important to note that fields like 7310, or the Option\u2019s Greek Theta, can take a few requests, or even a few moments to begin. That is because some values may not be readily available and must be calculated by Interactive Brokers before returning. Especially on less active strikes, this can take up to a minute before returning these fields.<\/p>\n\n\n\n

Requesting Historical Data<\/h4>\n\n\n\n

            With our live market data returning as intended, we can now move on to a historical market data request. In addition to our standard framework, I will add an endpoint variable, and set this equal to \u201chmds\/history\u201d for my historical data request. This is yet another GET request, so this will be built with a set of parameters: conid, period, bar and optionally, outsideRth and barType.<\/p>\n\n\n\n

            As opposed to live data, the historical data request will only allow a single conid at a time. As such, I will make a conid variable and set it equal to 265598 for AAPL. Now, I can make a period variable. This will determine the total range of data returned. It can scale from minutes, hours, days, weeks, months, or even years. But given our example today, I will set it equal to \u20181w\u2019 for 1 week. Then I can create my bar variable and set it equal to \u20181d\u2019, so I can see each day\u2019s bar for the whole week.<\/p>\n\n\n\n

            If I wanted to, I could make a request now and receive data without issue. However, I would like to move on to our optional parameters. I will start by setting outsideRth to \u2018true\u2019. By default, outsideRth is set to \u2018false\u2019 so we only see regular trading hours; however, we can choose to disable this. Next, I will create a barType variable and, in my case, set it equal to \u2018midpoint\u2019.<\/p>\n\n\n\n

Available values:<\/p>\n\n\n\n