The shopper’s advocate
Overcharged at checkout?
Make them pay it back.
Snap the shelf tag and your receipt. Checkout Cop catches the overcharge, shows your state’s rule, and hands you the exact words to get your money back. Short-weighted packages too.
- $0Free, always
- 50+DCEvery state
- ~1 minAt the desk
CHECKOUT COPResult
1 overcharge found
Michigan says you get
$5.50
- +$0.50
Peanut butter
Shelf $3.48 → charged $3.98
$0.50 back plus a $5.00 bonus
- OK
Whole milk
Shelf $2.97 → charged $2.97
What to say at customer service
“The shelf said $3.48 and I was charged $3.98. Under Michigan’s scanner law I’m owed the difference plus a $5.00 bonus.”
$5.64M
Paid by Walmart in August 2025 to settle California prosecutors' case alleging it charged more than posted prices and had inaccurate label weights. A settlement, with no admission of liability.
Source$45M
Walmart's class-action settlement, approved in 2024, over alleged overcharges on sold-by-weight goods and bagged citrus. Walmart denied wrongdoing.
Source$5
The most a Michigan store can owe you as a bonus for a single scanner mistake, on top of your refund. Many shoppers don't know to ask.
SourceWhat would the store owe you?
Try your own numbers. Nothing is saved or sent anywhere.
Overcharged $0.50 · Michigan says
$5.50
$0.50 back plus a $5.00 bonus: $5.50 total.
Check my real receipt →See it work
Fifty seconds. One overcharge caught.
A $3.98 charge on a $3.48 shelf price. Watch Checkout Cop catch it, cite Michigan’s law, and hand over the words that get $5.50 back.
Try it on your next receipt →Two ways we catch them. Both free.
Weight check
Is it really 16 oz?
- 1
Weigh it
Flat surface, scale zeroed. We verify your scale with coins or the store's inspection seal.
- 2
Snap the label and the scale
We read both photos. You confirm every number before anything is judged.
- 3
Get the legal verdict
Checked against NIST Handbook 133, the national rulebook for package weights, with the state agency to contact if it's short.
Price check
Did the register charge the shelf price?
- 1
Snap every shelf tag
As items go in your cart. We read each one and save it with the time: your proof.
- 2
Snap the whole receipt
A few photos or one screenshot. We match every tag to its line. You confirm.
- 3
Know what you're owed
In Michigan that's up to a $5 bonus. In Massachusetts and Connecticut the item can be free.
Prices on the shelf are changing. So are the laws.
CNBC · March 2026
Walmart digital price tags are coming to every US store by end of 2026
Read the source →
U.S. Senate, S. 3892 · 2026
Stop Price Gouging in Grocery Stores Act would ban digital shelf labels in grocery stores over 10,000 sq ft
Read the source →
Modern Retail · Oct 1, 2026
Maryland's dynamic pricing ban takes effect, with fines up to $25,000
Read the source →
Progressive Grocer · 2026
New Jersey passes bill banning surveillance pricing and pausing digital shelf labels in grocery stores
Read the source →
Sonoma County DA · August 2025
Walmart settles consumer protection case for scanner price overcharges and false advertising: $5.64M
Read the source →
ABC7 · July 2022
Bay Area inspectors found overcharges on 7% of items scanned at Walmart and 9% at Target
Read the source →
Your rights, in writing
In three states, the store owes you more than the difference.
Michigan
Refund + up to $5
The difference plus 10 times the overcharge, at least $1. Tell the store within 30 days.
Massachusetts
Free or $10 off
Rings up above the lowest posted price? $10 or under, the first one is free. Over $10, $10 off. Groceries and household goods.
Connecticut
It's free
Rings up above the posted price? You get one free, up to a value of $20.
Every other state: you’re owed the difference. We show you how to ask.
Catch it. Say it. Get paid.
Step 1
Catch it at checkout
Snap the receipt before you leave, while it's easy to fix.
Step 2
Get your money back
We give you the exact words to say at customer service.
Step 3
Know what you're owed
Your state's rules, including bonuses most shoppers never hear about.
Real cases, checked
Publicly reported weigh-ins, run through the same math as the tool above.
What Checkout Cop catches
Four kinds of checkout errors the law covers. Being honest about which ones are live today is part of the product.
Short-weight packages
Label says 16 oz, your scale says less. Checked against the real NIST Handbook 133 tolerance table.
Check this now →Price overcharges
Shelf tag said one price, register charged more. No tolerance applies under NIST Handbook 130, and three states pay you extra.
Check this now →Weighed with the tray
Deli or bulk items weighed with the tray, wrap, or ice still on the scale. This always needs a manual look.
Surveillance pricing
Prices set per shopper or changed on the fly. Maryland's dynamic pricing ban starts October 1, 2026, and other states are moving to limit it.
Why trust the result
Public tolerance tables. Every bracket comes from NIST Handbook 133/130. See exactly where.
You confirm every number. Nothing is judged until you confirm every number, whether you typed it or a photo was read.
We never shame stores. Checkout Cop does not rank, list, or publicly flag retailers by user reports, and won’t.
Honest about limits. Tare checks still need a human look, and a price check flags any “with store card” or multi-buy condition on the tag. Checkout Cop says so instead of forcing a confident-sounding answer it can’t back up.
FAQ
Is a Checkout Cop result legal advice?+
No. It's a math check against public NIST tolerance tables, based on the numbers you enter. Only your state weights and measures agency can make an official determination. See the disclaimer.
Is anything more than an ounce short illegal?+
Not always. There's no single one-ounce rule. The allowed shortfall depends on the product and the package size. For USDA-inspected meat and poultry like bacon, in packages from 7 oz to 3 lb, it is 1 oz. For most other foods it's smaller on small packages and bigger on large ones: 11/16 oz on a 16 oz package, about 1.1 oz on a 2 lb bag. Meat and poultry fall under the USDA and your state weights and measures office. Most other foods fall under the FDA and your state office. Inspectors also test a batch of packages, not one, so a single package slightly over the line isn't automatically a violation.
What if my scale isn't accurate?+
Verify it first with coins. See how on the data sources page. A cheap or uncalibrated kitchen scale can create a false result in either direction.
Does it cost anything?+
No. The weight check and the price check are both free, with no account required.
How is it free? Who runs it?+
An independent small publisher runs Checkout Cop. Reading pages show a few ads, mostly for our other websites. Ads never appear on the checks or your results, and no store or brand we check can advertise or change a result. See About us.
What if the app misreads a photo?+
Nothing counts until you confirm every number. Tap any number to fix it before you check.
Do I have to do this in the store?+
No, but it's easiest there. Snap the shelf tag before checkout and the receipt before you leave, then go to customer service. Noticed at home? Bring the receipt and your tag photo back. In Michigan you have 30 days. See what to do in every situation.
Do I need to talk to a manager?+
Usually not. Customer service or the self-checkout attendant fixes price errors every day. Ask for a manager only if they say no.
What if my receipt is long, or it's a digital receipt?+
Take it in parts, up to 4 photos, and we match every tag you saved to its line. Digital receipt in the store's app? Take a screenshot and choose it instead.
What does the store owe me if I was overcharged?+
Everywhere, the difference. In Michigan, the difference plus a bonus of 10 times the overcharge (at least $1, at most $5), if you tell the store within 30 days. In Massachusetts, an item $10 or under is free, and over $10 you get $10 off. In Connecticut, one item is free, up to a value of $20. See overcharge rights by state for the details and official sources.
What about online or delivered orders?+
Price: screenshot your cart when you order, then use the store app's refund or report-a-problem option. The bonus rules are written for prices posted in the store. Weight: the same legal limit applies as in the store. See what to do for online orders.
Can I use this to publicly call out a store?+
No, Checkout Cop doesn't publish or rank stores by user reports, and never will. A single unverified measurement displayed as a public accusation isn't fair to a store, and it isn't the same thing as a complaint filed with the agency whose job is to actually check.
Do you store what I type in?+
The type-it-in check runs entirely in your browser. The camera tools send each photo once to be read, then throw it away. We don't keep your photos, receipts, or prices. See the privacy policy.
Your next shopping trip
Don’t leave money at the register.
Free. No account. About a minute per check.