Frequently asked questions about Quandl.
1. What is Quandl?
Quandl is a platform covering millions of financial and economic time-series datasets from hundreds of sources. Our long-term mission is to make all numerical data on the internet easy to find and easy to use.
2. How does Quandl work?
Quandl has indexed millions of numerical datasets from around the internet. When you click on a particular dataset listed in our index, Quandl extracts the most recent version of that data from the source or from our cache, cleans it up, and gives it to you in whatever format you want.
3. How can I use Quandl to find data?
Simply type what you’re looking for into the Quandl search box. Quandl will give you a list of datasets that reference your search terms. The list includes information such as the original source of the data, the type of data and a brief description. Click on any result in the list to see the actual data in that dataset.
You can also explore our data using 'Collections'. Collections are groups of related datasets on specific subjects curated by Quandl users. Here are some examples of popular collections on Quandl:
Collections offer an easy way to find high-quality data on the subject of your interest. You can browse through all of our 75,000+ data collections from our home page.
4. What can I do with the data I’ve found?
You can view the raw data along with a graph of the data, right on our website. You can also see the original publisher of the data, the full source URL, and information about how recent the data is.
After viewing the data, you can transform it in a number of ways: choose specific start and end dates, change frequency, calculate row-on-row changes and percentage changes, normalize and more.
You can download the data in the format of your choice (XLS, CSV, HTML, JSON, XML), all at the click of a button. You can also export or embed a graph of the data.
Finally, you can access all of our data via our free API or through various packages that integrate Quandl with existing third-party tools.
5. What types of numerical data does Quandl cover?
Quandl currently covers only 'time-series numerical data', that is, data in the form of a historical trend or sequence. Here are some examples:
- GDP of the United States
- Inflation in China
- AAPL stock price
- Kansas City wheat futures
- Deforestation in Brazil
We don’t handle intraday data yet. Nor do we handle non-numerical data.
6. Where does Quandl get its data from?
Each dataset on Quandl is associated with a data source. Sources can be primary data publishers, curators, contributors, vendors or individual users. Here are some examples of popular sources on Quandl:
7. What fields or categories of data does Quandl cover?
Quandl’s data is mostly (but not exclusively) concentrated in the fields of financial markets, economics, society and demography.
8. What data formats can Quandl handle?
Quandl aims to be a universal translator for data formats. Our goal is for Quandl to accept numerical data no matter what format it happens to be published in. We are adding new data formats to Quandl’s parsing engine all the time.
9. How many datasets does Quandl cover?
Quandl currently covers approximately 8 million datasets, and that number is continually growing each day.
More About Data
10. How can I trust Quandl’s data?
Every dataset on Quandl includes a link back to an authoritative source for that data, allowing you to validate its quality and accuracy.
11. How recent / fresh is the data that I get from Quandl?
Every dataset page on Quandl has an indicator showing how recently the data was retrieved from its original source. It is our goal to always provide data in its freshest possible version. For daily datasets, we are never more than a few hours behind the source. For weekly, monthly and annual datasets, we are never more than a day behind the source.
12. Will a dataset that I find on Quandl always be available to me?
Yes. Every single dataset on Quandl has a permanent and unique name, dataset code and URL on Quandl. You will always be able to access data on Quandl through these permanent attributes – even if the original source is no longer available.
13. Can I suggest data to Quandl?
Absolutely. We welcome any and all suggestions for new data to index; please email us with your requests.
14. Can I add data to Quandl directly?
Not any more -- this function has been deprecated.
15. How do I leave feedback about Quandl?
Please email us with your comments, suggestions, bug reports, data requests, and any other feedback you’d like to share.
16. How can I help make Quandl better?
Quandl is a collaborative project, and we welcome all offers of help. Bug reports, feature requests, data uploads and code contributions are all greatly appreciated. Please email us to find out how you can get involved. Thank you for your support!