MISO offers a new way to find the data you and your organization need through the MISO Data Exchange. The MISO Data Exchange comprises APIs (Application Programming Interfaces) that enable users to access MISO Market Report data for use in their own applications.
Why is MISO offering APIs?
MISO has historically offered reports comprising analysis and status of market operations. These reports, available on the MISO website, are produced in a variety of formats for users to download and reformat. With the launch of the APIs in the Data Exchange, users now have an endpoint from which to collect and consume data in the way that best serves them.
Note: MISO will continue to make the market reports available on the public website for now but will eventually discontinue their availability in an effort to fully transition to the Data Exchange.
Who can access the Data Exchange?
Anyone with a profile on the MISO public website can create an account on MISO's Data Exchange. For detailed information on how to create an account and access the APIs, view the MISO Data Exchange User Guide in the Learning Center. If you do not have a Learning Center account, please refer to the Learning Center Access Knowledge Article for instructions on creating one.
What data is available?
The Data Exchange currently includes the following:
Pricing API
- Ancillary Services Market
- Day-ahead ExAnte Market Clearing Prices
- Day-ahead ExPost Market Clearing Prices
- Real-time ExAnte Market Clearing Prices
- Real-time ExPost Market Clearing Prices
- Energy Market
- Day-ahead ExAnte Locational Marginal Price
- Day-ahead ExPost Locational Marginal Price
- Real-time ExAnte Locational Marginal Price
- Real-time ExPost Locational Marginal Price
Load, Generation and Interchange API
- Load
- Day-ahead Combined Demand
- Energy Market Day-ahead Load Data
- Real-time LoadSE Demand
- Real-time FORECASTMW Demand
- Load Forecast Data for Given Market Date
- Generation
- Day-ahead Cleared Generation, Physical
- Day-ahead Cleared Generation, Virtual
- Day-ahead Offered Generation ECOMAX
- Day-ahead Offered Generation ECOMIN
- Day-ahead Generation Fuel Type
- Real-time Generation Fuel on the Margin
- Real-time Generation Fuel Type
- Committed ECOMAX Generation
- Offered ECOMAX Generation
- Real-time Generation Cleared
- Interchange
- Day-ahead Net Scheduled Interchange
- Real-time Net Scheduled Interchange
- Real-time Net Actual Interchange
- Historical Net Scheduled Interchange
Additional APIs will be added as the Data Exchange continues to grow.
Is there data mapping available?
Yes, data mapping is located here: Data Exchange Report to Endpoint Mapping.xlsx.
What if I can't find a specific data element?
All available data elements are documented in the Data Exchange Report to Endpoint Mapping document reference above. If you believe that a necessary data element is not provided, please submit a case through the Help Center.
When is the data refreshed?
Data is refreshed once a day. If the market date = current date, new data might not be available yet based on refresh times. Please refer to the following table for estimated data refresh times.
Data Type | Estimated Refresh Time |
Day-Ahead | ~6:45 PM GMT |
Real-Time | ~8:45 AM GMT |
How do I use the APIs?
Our APIs use a RESTful style with respective endpoints. Using the API, users make requests — known as calls — to retrieve specific data.
Refer to the MISO Data Exchange User Guide in the Learning Center and the API specifications in the API definition dropdown within the Data Exchange for more details.
Is there a call limit?
Yes, there is currently a 100 call/minute rate limit and a 24,000 call/day quota. Exceeding the rate limit will result in a "429 Too Many Requests" error and resets every minute. Exceeding the daily quota will result in a "403 Forbidden" error and further calls should be delayed according to the "Retry-After" header. The limits apply on a per-subscription basis.
What can I do about HTTP 500/5XX errors?
The Data Exchange is new, so there may be times when it is unable to service your initial call to an endpoint. Be sure to account for this possibility in your own application by implementing retry logic.
API Error Codes
| Error Code Number | Meaning | Solution |
| 400 Bad Request | This request is malformed - e.g. invalid JSON, missing fields, or wrong data types, data is not available. | Check/Validate syntax and required parameters |
| 401 Unauthorized | API KEY is missing, invalid or expired. API KEY is a long number that MISO gives to the user to allow them access to the data. | Include a valid API Key |
| 403 Forbidden | API KEY is correct, but you do not have permission to access the data | Contact the Help Center |
| 404 Not Found | The requested endpoint or resources doesn't exist | Double check URL, resource identifiers and versioning |
| 422 Unprocessable Entity | Request syntax is correct by data failed validation | Fix specific field errors (e.g., wrong format, missing values) as indicated in the API response |
| 429 Too Many Requests | Rate limit exceeded | Retry after the time specified |
| 500 Internal Server Error | Generic server-side failure | Retry after a brief delay |
| 502 Bad Gateway | Server acting as a gateway received an invalid response | Retry with exponential backoff, check service status |
| 503 Service Unavailable | API is temporarily unavailable (e.g. maintenance or overload) | Retry with exponential backoff, check service status |
| 504 Gateway Timeout | Gateway or proxy timed out waiting for upstream server | Retry later, optimize request |
What can I do about additional HTTP errors?
Make sure your API request follows the API specifications in the API definition dropdown within the Data Exchange.
Your account may require additional set-up to access the APIs. Refer to the MISO Data Exchange User Guide in the Learning Center to additional help, including requirements for API access.
Can I change the page size for API responses?
No, the page size cannot be changed at this time.
Can I specify additional date ranges within API calls?
No, this feature is not available at this time.
I'm unable to access the Data Exchange from outside the US. Can I get my country/region whitelisted?
If you provide your company's IP addresses, we can whitelist them for access. We do not provide global access otherwise.
Do the API keys for the Data Exchange expire?
The API keys do not expire or require revalidation, but the accounts they are tied to have account password that expire and require reset after 1 year. Existing API keys should continue to work regardless of account status.
Preliminary and final RT prices are offered through "Retrieve Energy Market Real-time ExPost Locational Marginal Price (LMP)" on the data exchange. What is the delay on the RT prices and how many days after the operating day will final prices be available?
RT LMPs are available by 8am EST the following day. It takes on average 3-5 days to finalize preliminary LMPs.
When will EPnode pricing both Day-Ahead and Real-Time be available through the MISO Data Exchange?
This information is scheduled to be available as an API in Q4 2025.
Who can I contact with questions?
For questions or assistance, please submit a case through the Help Center. When creating your case, select System or Technical Issues for the case category, IT Operations Center for the case type, and Public Data Reports and APIs for the case sub-type.