Emissions Test by State

Emissions Test by State is an independent reference and is not affiliated with any government agency. It quotes official text; it is not legal advice. Rules change, so confirm with the agency before you act.

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How this site works

The site does two things: it quotes official text about vehicle emissions testing, and it compares what you enter with the figures printed in those quotes. It never tells you what to do.

Where do the quotes come from?

From state environmental and motor-vehicle agency pages, one governor’s office news release, state statutes and administrative codes, state legislature pages, a few city and county programs, and the US Environmental Protection Agency. Each state page lists its sources and says what kind each one is. We hold 522 quotes from 124 pages and documents.

Before each update a script requests every source again, with a User-Agent that names this site, and looks for each quote word for word. Case, spacing, the style of quotation marks and dashes, and a stray space before a comma are ignored; nothing else is. A source that does not load counts as unverified, a failed check never replaces the last passing one, and the site is not rebuilt from a failed check. The last full check was November 11, 2026; that is the “read” date beside every quote. A read date says the words were on the page that day. It does not say the page is up to date.

List items. Many rules are printed as lists. A list item is shown with the heading or lead-in it sits under on its source, marked “Listed under”. The script also confirms, on the live page, that the item is printed after that heading, close to it, with none of the page’s other recorded headings or section breaks in between. That check can’t see a heading we never recorded, so a person reads the page too. Where a page prints the same list county by county and a line would not show which county it belongs to, we leave the line out.

Lines that go together. Where two official pages word the same point differently, or a line has a worked example or a qualification, the lines are bound together and shown together: on the state’s page, in the table and in the checker. We don’t pick one.

Dates. A year or an effective date appears only where the quoted words print it. Our own labels for a source carry no year. Everything else carries the date we read it.

What about program websites run by contractors?

Several programs have a public website that is not on a government address. We quote such a site only when a state government page (an agency page, the state’s statute site or its legislature’s site) links to it, and the script confirms that link on every check. The 6 sites used this way, with the page that links to each:

Where we could not read a state page that links to a program site, we did not quote the site, and the state’s page says so.

What does the checker do with my entries?

It looks up the lines we hold for the state you choose, shows them (leaving out only a line printed for a place other than the one you chose, and the older text kept apart on the state’s page), and makes plain comparisons with the figures printed in some of them:

That is all. The subtraction is a pointer to the quote, and the quote says what its figure means. A line printed for one county or area is shown for that place, and left out when you choose another. The checker has no limits or figures of its own (a weight of any length is compared digit for digit), runs in your browser, sends nothing anywhere and stores nothing.

What can’t this site tell me?

Whether your own vehicle has to be tested. That depends on details an agency holds and we don’t, and on rules we may not have been able to read. A state’s page can be incomplete or out of date at its source; where we found no line on a subject, the page says so, and a missing line is never a statement that no rule exists. The site doesn’t list testing stations, book tests or take payments.

Which official pages could we not read?

Some official sites refuse a plain request or answer it with a bot check, and some return next to no readable text. We identify ourselves honestly and don’t work around either. On November 11, 2026 these 22 pages did not open for our reader, and the script confirmed each answer again:

One state site answered our requests inconsistently, so the script can’t confirm a single answer for it. These are the requests and what happened when we made them:

What do our own words promise?

As a backstop, the build runs word filters over everything that is not a quote. They stop on wording that would tell a reader what to do or say a vehicle is or isn’t covered, on a dollar figure, on a year outside the read date, on a weight, an age or a test interval in our own words, and on anything that would make the site read like an agency. A filter catches careless edits. It can’t judge whether a quote is fairly used; a person reads the pages for that.

Corrections

Spot a mistake, a quote that has changed at the source, or an official page we missed? Email hello@emissionstestbystate.com with the page and a link to the official text. We fix verified errors. We can’t answer questions about an individual vehicle; the agency can.