How we source our data
Checkout Cop doesn’t invent tolerance numbers. Every bracket the check tool and case pages use traces back to one of these public, government-published sources.
Last checked September 2026: the weight, count, and USDA meat and poultry tables were compared line by line against the 2026 edition of Handbook 133.
NIST Handbook 133: Checking the Net Contents of Packaged Goods ↗
The core standard behind every weight, volume, and count check on this site (Tables 2-5, 2-6, 2-7, 2-9). This is the procedural guide state and local weights & measures inspectors use.
NIST Handbook 130: Uniform Laws and Regulations in Legal Metrology ↗
The model law behind the price-overcharge check, including the Section 9.1 exceptions to a single-item overcharge finding.
FSIS Labeling Policies (USDA) ↗
USDA's Food Safety and Inspection Service directs inspectors to NIST Handbook 133 (and Handbook 44) as the definitive reference for meat and poultry net-weight compliance. This is why USDA-sealed products get their own tolerance table (Table 2-9) instead of the general one.
NIST State Weights & Measures Directors directory ↗
The public directory behind our state agency list: who to actually contact if you want to file a complaint.
U.S. Mint coin specifications ↗
The official, government-published coin weights (a quarter is 5.670 g) that let anyone verify their own kitchen scale for free before trusting a reading from it.
Price overcharge laws
The price check uses these state rules, researched and checked against their official sources in September 2026. Everywhere else, you’re owed the difference. See rights by state.
Michigan: Michigan Scanner Law (MCL 445.903)
The store refunds the difference plus a bonus of 10 times the overcharge, at least $1 and at most $5.
Official sourceMassachusetts: Massachusetts item pricing rules (202 CMR 7.07)
You pay the lowest price shown on the shelf, sticker, or sign. If that price is $10 or less, the first item is free. If it's more than $10, you get $10 off the first item.
Official sourceConnecticut: Connecticut General Statutes § 21a-79
If an item rings up higher than the posted price, you get one of it free, up to a value of $20.
Official source
Verify your own scale first
Before trusting any weight reading, yours or a store’s, check the scale itself. Put it on a hard, flat surface, let it read zero with nothing on it, then place four quarters on it. Four quarters weigh 22.68 grams exactly, per the U.S. Mint. If your scale reads within about a gram of that, it checks out. If it’s off by more, any “short” reading from it needs a second, better scale before you treat it as real.
Filing a complaint
If a check comes back over the legal limit, the agency to contact is your state weights and measures office, usually inside the state Department of Agriculture. Find yours in the NIST directory linked above, or search “[your state] weights and measures complaint.” Bring your receipt, the product (with packaging), and your measurement.
Journalists and researchers: this page and the check tool are free to cite and link to. Questions: hello@checkoutcop.com.