21 Places to Find Free Datasets for Data Science Projects (Shared Article from Dataquest)

This article was originally written by Vik Paruchuri   For the original source click here.

If you’ve ever worked on a personal data science project, you’ve probably spent a lot of time browsing the internet looking for interesting datasets to analyze. It can be fun to sift through dozens of datasets to find the perfect one, but it can also be frustrating to download and import several CSV files, only to realize that the data isn’t that interesting after all. Luckily, there are online repositories that curate datasets and (mostly) remove the uninteresting ones.

In this post, we’ll walk through several types of data science projects, including data visualization projects, data cleaning projects, and machine learning projects, and identify good places to find datasets for each. Whether you want to strengthen your data science portfolio by showing that you can visualize data well, or you have a spare few hours and want to practice your machine learning skills, we’ve got you covered.

But first, let’s answer a couple quick, foundational questions:

What is a dataset?

A dataset, or data set, is simply a collection of data.

The simplest and most common format for datasets you’ll find online is a spreadsheet or CSV format — a single file organized as a table of rows and columns. But some datasets will be stored in other formats, and they don’t have to be just one file. Sometimes a dataset may be a zip file or folder containing multiple data tables with related data.

How are datasets created?

Different datasets are created in different ways. In this post, you’ll find links to sources with all kinds of datasets. Some of them will be machine-generated data. Some will be data that’s been collected via surveys. Some may be data that’s recorded from human observations. Some may be data that’s been scraped from websites or pulled via APIs.

Whenever you’re working with a dataset, it’s important to consider: how was this dataset created? Where does the data come from? Don’t jump right into the analysis; take the time to first understand the data you are working with.

Public Data Sets for Data Visualization Projects

A typical data visualization project might be something along the lines of “I want to make an infographic about how income varies across the different states in the US”. There are a few considerations to keep in mind when looking for a good data set for a data visualization project:

  • It shouldn’t be messy, because you don’t want to spend a lot of time cleaning data.
  • It should be nuanced and interesting enough to make charts about.
  • Ideally, each column should be well-explained, so the visualization is accurate.
  • The data set shouldn’t have too many rows or columns, so it’s easy to work with.

A good place to find good data sets for data visualization projects are news sites that release their data publicly. They typically clean the data for you, and also already have charts they’ve made that you can replicate or improve.

1. FiveThirtyEight

FiveThirtyEight is an incredibly popular interactive news and sports site started by Nate Silver. They write interesting data-driven articles, like “Don’t blame a skills gap for lack of hiring in manufacturing” and “2016 NFL Predictions”.

FiveThirtyEight makes the data sets used in its articles available online on Github.

View the FiveThirtyEight Data sets

Here are some examples:

2. BuzzFeed

BuzzFeed started as a purveyor of low-quality articles, but has since evolved and now writes some investigative pieces, like “The court that rules the world” and “The short life of Deonte Hoard”.

BuzzFeed makes the data sets used in its articles available on Github.

View the BuzzFeed Data sets

Here are some examples:

3. NASA

NASA is a publicly-funded government organization, and thus all of its data is public. It maintains websites where anyone can download its datasets related to earth science and datasets related to space. You can even sort by format on the earth science site to find all of the available CSV datasets, for example.

Public Data Sets for Data Processing Projects

Sometimes you just want to work with a large data set. The end result doesn’t matter as much as the process of reading in and analyzing the data. You might use tools like Spark or Hadoop to distribute the processing across multiple nodes. Things to keep in mind when looking for a good data processing data set:

  • The cleaner the data, the better — cleaning a large data set can be very time consuming.
  • The data set should be interesting.
  • There should be an interesting question that can be answered with the data.

A good place to find large public data sets are cloud hosting providers like Amazon and Google. They have an incentive to host the data sets, because they make you analyze them using their infrastructure (and pay them).

4. AWS Public Data sets

Amazon makes large data sets available on its Amazon Web Services platform. You can download the data and work with it on your own computer, or analyze the data in the cloud using EC2 and Hadoop via EMR. You can read more about how the program works here.

Amazon has a page that lists all of the data sets for you to browse. You’ll need an AWS account, although Amazon gives you a free access tier for new accounts that will enable you to explore the data without being charged.

View AWS Public Data sets

Here are some examples:

5. Google Public Data sets

Much like Amazon, Google also has a cloud hosting service, called Google Cloud Platform. With GCP, you can use a tool called BigQuery to explore large data sets.

Google lists all of the data sets on a page. You’ll need to sign up for a GCP account, but the first 1TB of queries you make are free.

View Google Public Data sets

Here are some examples:

  • USA Names — contains all Social Security name applications in the US, from 1879 to 2015.
  • Github Activity — contains all public activity on over 2.8 million public Github repositories.
  • Historical Weather — data from 9000 NOAA weather stations from 1929 to 2016.

6. Wikipedia

Wikipedia is a free, online, community-edited encyclopedia. Wikipedia contains an astonishing breadth of knowledge, containing pages on everything from the Ottoman-Habsburg Wars to Leonard Nimoy. As part of Wikipedia’s commitment to advancing knowledge, they offer all of their content for free, and regularly generate dumps of all the articles on the site. Additionally, Wikipedia offers edit history and activity, so you can track how a page on a topic evolves over time, and who contributes to it.

You can find the various ways to download the data on the Wikipedia site. You’ll also find scripts to reformat the data in various ways.

View Wikipedia Data sets

Here are some examples:

Public Data Sets for Machine Learning Projects

When you’re working on a machine learning project, you want to be able to predict a column from the other columns in a data set. In order to be able to do this, we need to make sure that:

  • The data set isn’t too messy — if it is, we’ll spend all of our time cleaning the data.
  • There’s an interesting target column to make predictions for.
  • The other variables have some explanatory power for the target column.

There are a few online repositories of data sets that are specifically for machine learning. These data sets are typically cleaned up beforehand, and allow for testing of algorithms very quickly.

7. Kaggle

Kaggle is a data science community that hosts machine learning competitions. There are a variety of externally-contributed interesting data sets on the site. Kaggle has both live and historical competitions. You can download data for either, but you have to sign up for Kaggle and accept the terms of service for the competition.

You can download data from Kaggle by entering a competition. Each competition has its own associated data set. There are also user-contributed data sets found in the new Kaggle Data sets offering.

View Kaggle Data setsView Kaggle Competitions

Here are some examples:

  • Satellite Photograph Order — a data set of satellite photos of Earth — the goal is to predict which photos were taken earlier than others.
  • Manufacturing Process Failures — a data set of variables that were measured during the manufacturing process. The goal is to predict faults with the manufacturing.
  • Multiple Choice Questions — a data set of multiple choice questions and the corresponding correct answers. The goal is to predict the answer for any given question.

8. UCI Machine Learning Repository

The UCI Machine Learning Repository is one of the oldest sources of data sets on the web. Although the data sets are user-contributed, and thus have varying levels of documentation and cleanliness, the vast majority are clean and ready for machine learning to be applied. UCI is a great first stop when looking for interesting data sets.

You can download data directly from the UCI Machine Learning repository, without registration. These data sets tend to be fairly small, and don’t have a lot of nuance, but are good for machine learning.

View UCI Machine Learning Repository

Here are some examples:

  • Email spam — contains emails, along with a label of whether or not they’re spam.
  • Wine classification — contains various attributes of 178 different wines.
  • Solar flares — attributes of solar flares, useful for predicting characteristics of flares.

9. Quandl

Quandl is a repository of economic and financial data. Some of this information is free, but many data sets require purchase. Quandl is useful for building models to predict economic indicators or stock prices. Due to the large amount of available data sets, it’s possible to build a complex model that uses many data sets to predict values in another.

View Quandl Data sets.

Here are some examples:

Public Data Sets for Data Cleaning Projects

Sometimes, it can be very satisfying to take a data set spread across multiple files, clean them up, condense them into one, and then do some analysis. In data cleaning projects, sometimes it takes hours of research to figure out what each column in the data set means. It may sometimes turn out that the data set you’re analyzing isn’t really suitable for what you’re trying to do, and you’ll need to start over.

When looking for a good data set for a data cleaning project, you want it to:

  • Be spread over multiple files.
  • Have a lot of nuance, and many possible angles to take.
  • Require a good amount of research to understand.
  • Be as “real-world” as possible.

These types of data sets are typically found on aggregators of data sets. These aggregators tend to have data sets from multiple sources, without much curation. Too much curation gives us overly neat data sets that are hard to do extensive cleaning on.

10. data.world

data.world describes itself at ‘the social network for data people’, but could be more correctly describe as ‘GitHub for data’. It’s a place where you can search for, copy, analyze, and download data sets. In addition, you can upload your data to data.world and use it to collaborate with others.

In a relatively short time it has become one of the ‘go to’ places to acquire data, with lots of user contributed data sets as well as fantastic data sets through data.world’s partnerships with various organizations includeing a large amount of data from the US Federal Government.

One key differentiator of data.world is the tools they have built to make working with data easier – you can write SQL queries within their interface to explore data and join multiple data sets. They also have SDK’s for R an python to make it easier to acquire and work with data in your tool of choice (You might be interested in reading our tutorial on the data.world Python SDK.)

View data.world Data sets

11. Data.gov

Data.gov is a relatively new site that’s part of a US effort towards open government. Data.gov makes it possible to download data from multiple US government agencies. Data can range from government budgets to school performance scores. Much of the data requires additional research, and it can sometimes be hard to figure out which data set is the “correct” version. Anyone can download the data, although some data sets require additional hoops to be jumped through, like agreeing to licensing agreements.

You can browse the data sets on Data.gov directly, without registering. You can browse by topic area, or search for a specific data set.

View Data.gov Data sets

Here are some examples:

12. The World Bank

The World Bank is a global development organization that offers loans and advice to developing countries. The World Bank regularly funds programs in developing countries, then gathers data to monitor the success of these programs.

You can browse World Bank data sets directly, without registering. The data sets have many missing values, and sometimes take several clicks to actually get to data.

View World Bank Data sets

Here are some examples:

13. /r/datasets

Reddit, a popular community discussion site, has a section devoted to sharing interesting data sets. It’s called the datasets subreddit, or /r/datasets. The scope of these data sets varies a lot, since they’re all user-submitted, but they tend to be very interesting and nuanced.

You can browse the subreddit here. You can also see the most highly upvoted data sets here.

View Top /r/datasets Posts

Here are some examples:

14. Academic Torrents

Academic Torrents is a new site that is geared around sharing the data sets from scientific papers. It’s a newer site, so it’s hard to tell what the most common types of data sets will look like. For now, it has tons of interesting data sets that lack context.

You can browse the data sets directly on the site. Since it’s a torrent site, all of the data sets can be immediately downloaded, but you’ll need a Bittorrent client. Deluge is a good free option.

View Academic Torrents Data sets

Here are some examples:

  • Enron emails — a set of many emails from executives at Enron, a company that famously went bankrupt.
  • Student learning factors — a set of factors that measure and influence student learning.
  • News articles — contains news article attributes and a target variable.

Bonus: Streaming data

It’s very common when you’re building a data science project to download a data set and then process it. However, as online services generate more and more data, an increasing amount is generated in real-time, and not available in data set form. Some examples of this include data on tweets from Twitter, and stock price data. There aren’t many good sources to acquire this kind of data, but we’ll list a few in case you want to try your hand at a streaming data project.

15. Twitter

Twitter has a good streaming API, and makes it relatively straightforward to filter and stream tweets. You can get started here. There are tons of options here — you could figure out what states are the happiest, or which countries use the most complex language. We also recently wrote an article to get you started with the Twitter API here.

Get started with the Twitter API

16. Github

Github has an API that allows you to access repository activity and code. You can get started with the API here. The options are endless — you could build a system to automatically score code quality, or figure out how code evolves over time in large projects.

Get started with the Github API

17. Quantopian

Quantopian is a site where you can develop, test, and operationalize stock trading algorithms. In order to help you do that, they give you access to free minute by minute stock price data. You could build a stock price prediction algorithm.

Get started with Quantopian

18. Wunderground

Wunderground has an API for weather forecasts that free up to 500 API calls per day. You could use these calls to build up a set of historical weather data, and make predictions about the weather tomorrow.

Get started with the Wunderground API

Bonus: Personal Data

The internet is full of cool data sets you can work with. But for something truly unique, what about analyzing your own personal data? Here are some popular sites that make it possible to download and work with data you’ve generated.

19. Amazon

Amazon allows you to download your personal spending data, order history, and more. To access it, click this link (you’ll need to be logged in for it to work) or navigate to the Accounts and Lists button in the top right. On the next page, look for the Ordering and Shopping Preferences section, and click on the link under that heading that says “Download order reports”.

Here is a simple data project tutorial that you could do using your own Amazon data to analyze your spending habits.

20. Facebook

Facebook also allows you to download your personal activity data. To access it, click this link (you’ll need to be logged in for it to work) and select the types of data you’d like to download.

Here is an example of a simple data project you could build using your own personal Facebook data.

21. Netflix

Netflix allows you to request your own data for download, although it will make you jump through a few hoops, and warns the process of collating your data may take 30 days. As of the last time we checked, the data they allow you to download is fairly limited, but it could still be suitable for some types of projects and analysis.

Next steps

In this post, we covered good places to find data sets for any type of data science project. We hope that you find something interesting that you want to sink your teeth into!

If you do end up building a project, we’d love to hear about it. Please let us know!

At Dataquest, our interactive guided projects are designed to help you start building a data science portfolio to demonstrate your skills to employers and get a job in data. If you’re interested, you can signup and do our first module for free.

At Dataquest, our interactive guided projects are designed to help you start building a data science portfolio to demonstrate your skills to employers and get a job in data. If you’re interested, you can signup and do our first module for free.

If you liked this, you might like to read the other posts in our ‘Build a Data Science Portfolio’ series:

By CJ Sanchez (He/Him)
CJ Sanchez (He/Him) Career Coach