Chicago publishes a vast amount about itself — who's paid what, who owns what, what's being built, and what's gone wrong. This guide maps what "Chicago open data" is, the datasets that matter most, how to access them, who relies on them — and, honestly, where ALKARTIS does and doesn't operate today.
Open data is public information a government publishes proactively, in reusable formats, for anyone to access without a formal request. In Chicago, most of it flows through the Chicago Data Portal (data.cityofchicago.org) — the city's central catalog, with downloads and an API for each dataset. People search for it as "Chicago open data," "open data Chicago," or "opendata chicago" — it's all the same thing.
Chicago's Open Data Executive Order (2012-1) directed departments to publish their public data openly through the portal.
Thousands of datasets exist, but a handful carry most of the questions people actually ask:
One of the most-used open datasets anywhere — reported crime incidents across the city, geocoded and updated regularly.
Resident-filed requests, connected by type and location across every ward.
Department of Buildings permit filings — where construction is moving, block by block.
Citywide parcel and zoning data. Property assessments are held by the Cook County Assessor.
Current employee names, salaries, and position titles, published by the city.
Restaurant and food-establishment inspection results from the Department of Public Health.
There are three common routes in. You can browse and download any dataset from the portal as a CSV, JSON, or GeoJSON file. You can query datasets programmatically — the portal exposes an API for each one, so developers and researchers can filter and pull specific records or geographies without downloading whole files. And for authoritative single-record lookups, individual agency systems give you the official record for one address or entity.
Each route trades convenience for effort. Browsing is easy but returns a raw table with no context; the API is powerful but assumes you can write queries and reconcile fields across agencies that rarely share a common identifier.
The hard part of open data isn't access — it's that a dataset is not an answer. A payroll file gives you a number, not whether it's unusual for the role. A permit gives you an address, not whether it's one of dozens on the same block this quarter. A violation names a building, not whether the same owner has a pattern of them across a portfolio held under different LLCs.
Turning records into answers takes cross-referencing datasets that were never designed to be joined, establishing a baseline so a single number has context, and tracing every figure back to its source so it can be checked. That connective layer is what we call Information Intelligence — the engine behind every ALKARTIS product.
ALKARTIS is live in Philadelphia, not yet in Chicago. Our products are built specifically around Philadelphia's public records today; Chicago is on our aspirational roadmap rather than committed to a timeline. If your organization needs connected Chicago intelligence — landlord portfolios, payroll patterns, permit signals, block-level activity — our enterprise and custom analysis engagements are how a new city comes online. Tell us what you need and we'll scope it.
Chicago Data Portal is Chicago's open data portal, where city agencies publish public datasets — 311 requests, permits, property records, payroll, crime, and more — free for anyone to access, download, and reuse.
Yes — free to browse, download, and use, with an API for most datasets. The challenge isn't access; it's cleaning, cross-referencing, and interpreting raw exports across agencies that don't share common identifiers.
Browse and download datasets from the portal as CSV, JSON, or GeoJSON; query them through the portal's API; or use individual agency systems for the authoritative record on a single address or entity.
Not yet. ALKARTIS products are built around Philadelphia's public records today, and Chicago is on our aspirational roadmap rather than committed to a timeline. For organizations that need connected Chicago intelligence, our enterprise and custom analysis engagements are how a new city comes online — you can request Chicago directly.