PriceGap

Is the store showing you a different price?

PriceGap is a free Chrome extension. On any product page it loads the same page again as a stranger, with no cookies and no login, and puts the two prices side by side. It says why they differ (your store, your membership, the seller, or you), it checks whether the crossed-out "was" price is one anybody pays, and it keeps the record: a public wall, by store, week by week, of what personalised pricing looks like when it starts.

Coming to the Chrome Web Store

Free. No account. Each result is shared anonymously (the store, the two prices and the cause, never the link or you) so the wall below can exist; one switch turns that off. There is also a silent mode: nothing drawn, ever; it only collects the anonymous pricing data.

You see

$22.64

Fresh visitor sees

$26.11

Your account gets $3.47 less (13.3%). Keep it.

A real check on a 10-pack of moving boxes. A business discount was doing the work. Sometimes it goes the other way.

How it works

Three steps, about ten seconds, nothing to sign up for.

STEP 1

Open a product page

Any store. Press the PriceGap button. It reads the price you are being shown, right off the page.

STEP 2

It visits the page as a stranger

The same address is loaded again with no cookies, no login and no history. Some stores block that, so it can also open the page in a private window and read the price there. Do not be alarmed if a private (incognito) window appears minimized while you browse a store you have automatic checks on for: that is PriceGap reading the stranger's price, and it closes itself.

STEP 3

You see both prices

Same, cheaper for you, or dearer for you, with the percentage. Delivery counts: when both pages show a delivery line, the comparison is item plus delivery, because a lower sticker with paid delivery can cost more all in. If the stranger's price is lower, one button opens that page in a private window so you can buy at that price.

Three ways to run it

Switch on automatic checks for a store and pick how much you want to see. The checks and the anonymous record are the same in all three.

EVERY CHECK

See every answer

A small card beside the price and a badge on the toolbar on every product page checked, gap or no gap. The default.

ONLY WHEN SOMETHING DIFFERS

See the exceptions

The card appears only for a price gap, a different store, or a crossed-out price that does not hold. Same price, nothing drawn.

SILENT

Collect only

Nothing is ever drawn on a page or the toolbar. PriceGap runs in the background on the stores you switched on and only collects the anonymous pricing record for the wall: the store, the two prices and the cause, never the link or you. Open the popup on a page if you want to see its result. For people who want the record kept and never want to be interrupted.

What makes a price yours

Most online prices are not one number. These are the things that change what you see, roughly in order of how often they do it, with what PriceGap can and cannot tell apart.

Your account or membership

Business accounts, Prime, Pro programmes, store cards and "member prices" all show a different number once you are logged in. Example: the same 10-pack of moving boxes read $22.64 on an Amazon Business account and $26.11 to a stranger; the account was getting a 7% business discount. This is exactly what PriceGap measures.

Where the store thinks you are

Big-box stores price per store, and the site guesses your store from your address or your network. Example: Home Depot priced one RYOBI kit for store #8119 in Phoenix and would price it differently for a store in Vail. PriceGap reads the store on both sides and says "location, not you" when they differ.

Coupons and offers tied to you

Clip-a-coupon, first-order codes, "we miss you" emails and cart-abandonment discounts change your price and nobody else's. Example: an Amazon coupon you clipped shows as a lower price on your page and a higher one to a stranger, in your favour. The wall counts these as "charged less".

Quantity tiers

Business accounts often see "2 for 9% off" that a stranger never sees. PriceGap compares the single-unit price on both sides, so a tier only you can see reads as the same price. An honest blind spot, on the list to fix.

Time and demand

Prices move by the hour on the biggest stores; Amazon changes millions a day. A sale that starts between your page load and the check reads as a gap that is really just time. Press Check again and it clears.

Device, browser and history

The most-repeated claim and the hardest to prove. Some travel sites have been documented showing different results by device; most retail stores have not been. A fresh visitor has no history and no device fingerprint the store recognises, so if the stranger's price is lower and nothing above explains it, this is what is left.

The Price Gap Wall

A record, kept over time, of what makes a price differ between a signed-in shopper and a stranger. Every shared check says why: personal (same store, same seller, no membership on the page, and still a different price: the only kind that can be about you), member (a business account, Prime or Walmart+ price), location (the two sides read different stores), seller (a different name in the buy box). And every crossed-out "was" price on the shopper's page is checked against what a stranger pays: inflated means nobody pays the figure the discount is measured from. Ranked by personal gaps. A store appears once it has ten checks. Item price, before delivery.

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Store	Checks	Personal, more	Personal, less	Member price	Location	Seller	Same	Inflated "was"	Biggest gap

What it does and does not do

What it collects

One anonymous record per check: the store's domain, a one-way hash of the product, the two prices, the currency, and the extension version.
That is on by default, the popup tells you so the first time, and the switch under every result turns it off.
That is the whole list. See the privacy policy.

What it never collects

The page address. The hash cannot be turned back into it.
Who you are. There is no account, no login, no user id.
Your history, your cookies, your other tabs.
No ads, no affiliate links, no selling anything to anyone.

Honest limits

A gap is not always about you, and mostly it is not. Home Depot and Walmart price by store; PriceGap reads the store on both sides, and on Walmart it reads the stranger again at your store so pickup prices compare like for like. Amazon Business, Prime and Walmart+ get real, disclosed member prices; those are filed as member prices. What we have measured so far (2026-09-17): 24 Walmart items signed in, all the same price as a stranger at the same store; 44 Amazon items on a Business account, 15 cheaper, none dearer. The per-person pricing regulators have documented is in apps like Instacart and the ride apps, which a browser extension cannot read. The wall exists so the day a store you can read starts doing it, the line moves and somebody sees it.
The discount you can check today is the "was" price. "-33% off list price $10.99" on a page where a stranger pays $9.97 is a real 26% discount measured from a number nobody pays. PriceGap grades every crossed-out price against the stranger's, on every store it can read, no personalisation required.
Some stores block every anonymous visit. The private-window check gets past most of that. When it cannot, the extension says so rather than guessing a number.
Prices move. A sale that starts between your page load and the check reads as a gap. Press Check again.
The wall is what people chose to share. People install this because they suspect something, so it leans toward stores with gaps. Treat it as a place to look, not a verdict.