Naperville, Illinois carries a Very Low crime rating. Pittsburgh, Pennsylvania carries Moderate-High. Those two labels sit at nearly opposite ends of WhereAtHome's seven-tier scale, and it's worth knowing exactly what that gap does — and doesn't — mean before you let it decide where you move.
A crime tier is a compressed summary of police-reported data. It's genuinely useful for a first-pass comparison. It is not a verdict on a neighborhood, a household's actual risk, or a full account of what "safe" means to you. This guide explains where the underlying data comes from, how WhereAtHome turns it into a tier, and where a citywide number needs local follow-up before it should change anyone's decision.
Where the rating comes from
Crime tiers are built from data reported through the FBI's crime statistics program. More than 19,000 law-enforcement agencies nationwide contribute, per the FBI's Uniform Crime Reporting overview — but except for federal agencies, participation is voluntary, and coverage varies by state, agency, and month. Most current reporting flows through the National Incident-Based Reporting System (NIBRS), which captures more detail per incident than the older summary-count system it replaced. The public portal for this data is the FBI Crime Data Explorer.
That reporting chain matters for interpretation. An event has to come to an agency's attention, get recorded under a program definition, and make it into a submission before it shows up in any published rate. Differences in community reporting habits, agency recordkeeping, and participation can all move a number — a higher count doesn't, by itself, tell you which of those factors was involved.
WhereAtHome's seven tiers, in full
Every city's crime rating maps to one of exactly seven tiers, each with a fixed score:
| Tier | Score | Rough read |
|---|---|---|
| Very Low | 95 | Among the safest cities we track |
| Low | 80 | Meaningfully below-average reported crime |
| Moderate-Low | 65 | Somewhat below the national picture |
| Moderate | 50 | Close to typical |
| Moderate-High | 35 | Somewhat above the national picture |
| High | 20 | Meaningfully above-average reported crime |
| Very High | 10 | Among the highest reported rates we track |
This factor carries 20% weight in the overall WhereAtHome Score — the same weight as housing affordability, and more than commute or walkability. These seven labels and their scores are the complete list — nothing else is a valid crime rating in our data, which is exactly why the next section matters.
Naperville: what "Very Low" is built from
Naperville's Very Low rating corresponds to 9.3 reported incidents per 1,000 residents, sourced from 2024 FBI Crime Data Explorer data, and scores 95 — the top of the scale. Combined with strong income and school numbers, it's a large part of why Naperville shows up on national "best places to live" lists as often as it does. But a citywide per-capita figure is still an average: it doesn't distinguish between a quiet residential block and a commercial strip a few miles away, and it can't tell you how the number was trending in the months before or after the reporting period it covers.
Pittsburgh: what "Moderate-High" does and doesn't mean
Pittsburgh's Moderate-High rating scores 35 — well below Naperville, but also well above the bottom of the scale. That distinction matters: Moderate-High is not the same category as High or Very High, and a single tier gap can sit close to a cutoff between two ratings that are, in practice, not that different. Before reading too much into Pittsburgh's tier alone, it's worth checking the same things you'd check for any city: which offense categories are included, which time period the data covers, and whether the reporting agency's boundary matches the city limits you have in mind. Our WhereAtHome Score methodology guide shows exactly how much this one component moves a city's total score relative to housing, income, and the rest.
An unrecognized rating is a bug to fix, not a guess to make
The seven tiers above are the only labels the scoring system recognizes. If a data source ever reports a crime rating that isn't one of these seven exact strings, the scoring function doesn't quietly round it to Moderate or drop it from the average — it throws an error. That's a deliberate choice: a new or misspelled tier is a data-pipeline problem that needs a human to look at it immediately, not a gap that should silently resolve itself into a plausible-looking number. If you ever see a city with no crime component in its score breakdown at all, that's the system declining to guess rather than a sign the city is unusually dangerous or unusually safe.
Why a citywide number still needs a neighborhood follow-up
Crime data is reported by law-enforcement agency, and an agency's jurisdiction doesn't always match the city boundary you're picturing. A police department might cover only part of a metro area, or a county agency might blend a dense urban core with sparsely populated unincorporated land. City totals also average across neighborhoods with very different land use — a downtown entertainment district and a quiet suburb-style neighborhood can sit inside the same citywide rate despite being nothing alike day to day. The FBI's own guidance is direct about this: its caution against ranking jurisdictions warns that simple rankings omit the many local conditions that shape a number, and the Bureau of Justice Statistics' overview of the nation's two crime measures is a good reminder that even police-reported data and victimization surveys — a second, independent measure — don't always move together.
A short audit before you trust the comparison
Before letting a crime tier meaningfully influence a decision:
- Check both cities' full component breakdown, not just the tier label, on the compare tool.
- Confirm the reporting year and note that FBI data can be revised after initial publication.
- Remember that a citywide average can't answer a block-level question — plan to look at neighborhood-level data or local reporting for any specific area you're seriously considering.
- Treat a one-tier gap as a meaningful signal, but a difference near a tier boundary as closer than the labels suggest.
A crime tier is a fast way to narrow a list of cities. It's not a substitute for visiting a neighborhood, talking to people who live there, or checking a local police department's own published data before you commit to an address. Used that way — as the first filter rather than the final word — a seven-tier scale built on real FBI data is a genuinely useful starting point, not a shortcut around the rest of the research.
