reference · data by interest

Data: grab what grabs you

Don't hunt for the "right" dataset — take the one you actually care about. Here are aggregators that hold anything, plus picks by theme. Each has what it is and what to ask it. Start with any of them.

Where to find anything

Aggregators and search engines for any topic. Bookmark a couple — useful at any level.

Kaggle Datasets

CSV · sign-up

The biggest hub: hundreds of thousands of datasets + competition data. Each has discussions, example notebooks and a free online coding environment.

Tip: each dataset has a Code tab with other people’s notebooks — a great way to see what questions people ask of this data.

Hugging Face Datasets

text/image/audio · Python

The main AI hub: thousands of datasets (text, images, audio) next to models. Everything loads in one line of Python with streaming and caching.

Google Dataset Search

search · free

Google tuned for datasets: searches the whole web — government portals, research repos, Kaggle. Know the topic but not where the data is? Start here.

Data Is Plural

newsletter + archive

A weekly newsletter of curious datasets: 5 a week, 400+ issues since 2015. A searchable archive — a trove of offbeat topics.

Tip: subscribe and pick something that grabs you each week. Motivation beats picking the “correct” dataset.

A huge categorized list of open datasets by topic (biology, finance, sport, transport…). All in one place, with links.

AWS Open Data

big data · S3

A registry of large open datasets in Amazon’s cloud: satellites, genomics, weather, transport. Often terabytes — for when you want to feel real scale.

BigQuery Public Datasets

SQL in cloud · 1 TB/mo free

Public datasets you query with SQL right in BigQuery: Wikipedia, weather, genomics, city data. Free tier: 1 TB of queries per month.

UCI ML Repository

tabular · small

One of the oldest repos: clean, tidy tabular datasets for the classics (classification, regression). Perfect when you want something small and clear.

Games

If you game — start here. The data is familiar and questions write themselves.

Steam Games 2021–2025

65k+ games · CSV

A fresh dump: 65,000+ Steam games (2021–2025) with genres, prices, tags. Great for your first aggregates and groupings.

Questions
  • Which genres are pricier on average, and which are near-free?
  • Is the indie share growing year over year?
  • Does price actually correlate with rating?

Steam Reviews (6.4M)

6.4M reviews · CSV

6.4M player reviews labelled “recommend / not” — a ready playground for text analytics and NLP.

Questions
  • What do negative reviews of a given game complain about most?
  • How did review sentiment shift after patches?
  • Does the tone differ between indie and AAA?

Steam Games + Reviews + Rankings

290 games · ~990k reviews

290 games with descriptions, genres, ratings and nearly a million reviews — handy for linking “game traits” to “player reaction”.

Questions
  • Which genres get the highest share of positive reviews?
  • Is there a link between price/release date and rating?

Music & film

Mini recommender systems and taste analysis — very tangible.

MovieLens

100k–32M ratings

The recommender classic: film ratings + genres and tags, from 100k to 32M rows. Perfect for your first JOINs — start with the small version.

Questions
  • Which genres consistently hold a high rating?
  • Do viewer tastes shift over the years?
  • Which films are “underrated” — few ratings, but high?

IMDb Datasets

TSV · official · large

IMDb’s official non-commercial dumps: films, series, ratings, actors and roles. Lots of data — good practice for cleaning and multi-table joins.

Questions
  • Is there a link between runtime and rating?
  • In which decade were series “stronger” by score?
  • Which actors appear most in top-rated films?

Spotify Tracks

114k tracks · 125 genres

114,000 tracks with audio features: danceability, energy, tempo, “mood” (valence), popularity. Also mirrored on Hugging Face.

Questions
  • How does your favourite genre differ from the rest by features?
  • How is “energy” related to popularity?
  • Can you guess the genre from the features?

Product & startup

The most hireable. Data behaves like a real product: orders, users, funnels, churn.

Olist — Brazilian E-Commerce

100k orders · 9 CSV · 45 MB

Real (anonymized) data of a Brazilian marketplace, 2016–2018: 100,000 orders across 9 linked tables — orders, customers, products, sellers, payments, reviews, geolocation. Essentially a mini-model of a real product — this is what product SQL is actually taught on.

Tip: fun detail — company names in the reviews are replaced with houses from Game of Thrones.
Questions
  • Top categories by revenue and month-over-month growth?
  • What does the funnel look like: order → payment → delivery?
  • What drives a bad review most — delivery delay? shipping cost?
  • Do customers return, and which ones (retention by customer_unique_id)?

Telco Customer Churn

1 CSV · 176 KB

A compact churn classic: plans, services, tenure, left/stayed. Small and clear — good for segmentation and your first predictions.

Questions
  • Who churns more — and by which traits?
  • Which services keep a customer?
  • Can you flag an at-risk group in advance?

Online Retail (UK)

~540k transactions · CSV

Real transactions from a UK online shop: receipts, products, quantities, countries. A classic for RFM analysis and cohorts.

Questions
  • Who are your best customers by RFM?
  • What does monthly sales seasonality look like?
  • Which products are most often bought together?

Event-stream generators like a streaming service (logins, plays, purchases): EventSim, Lenses Datagen, Mockingbird. You generate the data yourself — ideal for product metrics.

Questions
  • What DAU/WAU does the “product” have, and how do they grow?
  • What does the weekly retention curve look like?
  • Where do users drop in the signup → activation → payment funnel?

Web, trends & open source

Huge datasets that let you honestly say "I've worked with billions of rows." Some run right in your browser — nothing to install.

ClickHouse Playground

35+ datasets · 220+ examples · no install

Write SQL right in your browser against 35+ real datasets — Reddit and Hacker News posts, GitHub events, NOAA weather, forex. Each one ships with 220+ ready-made queries, so you can learn by taking apart someone else's SQL without installing a thing.

Questions
  • What time of day does Hacker News peak?
  • Which programming languages are growing by commit count on GitHub?
  • What pulls the most upvotes on Reddit?

GH Archive

billions of events · hourly

Every public GitHub action, logged hour by hour: commits, stars, PRs, forks. Load it into BigQuery or ClickHouse — the kind of scale that backs up "I've worked with big data."

Questions
  • When during the week do developers peak?
  • How did a specific popular repo grow its stars over time?
  • Which technologies are gaining, and which are fading?

Wikimedia EventStreams

live stream · SSE · free

A live feed of Wikipedia edits as they happen, over Server-Sent Events. The data is flowing right now — perfect for your first taste of real streaming.

Questions
  • How many edits per minute, and in which language editions?
  • Which pages are being edited most right this second?
  • Bots or humans — who's busier?

World & society

If the "serious" topics pull you in, this is where clean data meets ready-made examples of turning numbers into a story.

Our World in Data

CSV + ready-made charts · free

Health, climate, economy, population — by country and year, with polished visualizations and a full data catalog to pull from. It teaches you to tell a story with numbers and to show uncertainty honestly.

Questions
  • How does a country's income relate to life expectancy?
  • What happened to CO₂ emissions over the last 30 years?
  • Where is population growing fastest, and why?

FiveThirtyEight Data

CSV + articles · GitHub

Clean datasets behind their stories on sports, politics, and culture — all posted on GitHub. The trick: each one ships with the article that used it, so you can reproduce the analysis and then dig deeper.

Questions
  • Reproduce their analysis — then find what they missed.
  • Does the conclusion hold if you slice the data differently?
  • Which chart would tell the same story better?

World Bank Open Data

macro · API · free

Global economy and development by country: GDP, population, education, energy — hundreds of indicators spanning decades. It comes with a friendly API, so you can pull the data straight into your code.

Questions
  • How has the income gap between regions changed?
  • Is there a link between education and life expectancy?