Total In-Basket $0.00 Under budget
Real Dollar Savings $0.00 0% vs 30-day avg
Phantom Markup $0.00 Inflated list anchor
Deal Integrity Rating -- 0 items active
Live Deal Audit & Price Breakdown
Sale Price True Savings Phantom Markup
Select items manually or click Solve Optimal Basket to maximize genuine savings under your budget cap.

How Modern Major Sales Events Distort Discounts

During headline promotional cycles—such as Amazon Prime Day, Cyber Week, and seasonal clearance marathons—retail platforms and third-party marketplace sellers exploit price anchoring. The sticker price (often labeled "MSRP" or "List Price") is frequently an artificial reference point that the product hasn't sold at for months.

The "Phantom Markup" Trap

Retailers advertise a "45% discount" off a $200 MSRP ($110 sale price). However, pricing crawlers and historical trackers reveal the item has maintained an everyday street price of $125 for the previous 90 days. The genuine savings is only $15 (12%), not $90.

True Savings Calculation

True deal integrity measures the spread between the actual 30-day rolling baseline price and the flash sale price. When list price exceeds the 30-day average, the excess is defined as Phantom Markup.

The Mathematics Behind the Basket Knapsack Optimizer

Shoppers entering mega-sales face a classic bounded knapsack problem. You possess a hard fiscal constraint (e.g., a $450 budget) and a wishlist of candidate products, each with two distinct vectors:

Instead of randomly filling a cart with high-percentage cosmetic discounts that burn your capital on phantom markups, our client-side dynamic solver calculates the optimal combination of items that strictly satisfies:

Minimize: [Max Budget − Total Spend] ≥ 0
Maximize: ∑ (True Dollar Savings_i × Utility Weight_i)

This ensures every dollar deployed captures the steepest verifiable price drops on items you already intended to purchase.

Frequently Asked Questions About Sales Integrity

How is the 30-day baseline price determined?
In our preset library, 30-day baselines are derived from verified non-promotional rolling median sales prices across verified tech retailers. When entering custom items, inspect third-party price history charts (such as CamelCamelCamel or Keepa) to find what the item traded at three to four weeks prior to the promotional event.
Why does the tool show a negative "Deal Integrity Rating" on some items?
If a seller raised the price above normal street levels prior to the sale and then offered a nominal coupon, the "sale" price can actually be higher than the 30-day average. The tool flags these predatory listings with an Integrity Score below 40% and a red warning badge.
Are my shopping list inputs and budgets sent to any external server?
No. The Deal Integrity & Basket Optimizer operates entirely locally in your web browser using client-side JavaScript. No wishlist details, pricing records, or financial limits are uploaded or stored remotely.
How can I export my optimized shopping list?
Use the "Export CSV" button in the navigation or "Download Audit Report" in the bottom action bar. Both options instantly compile your vetted purchases, exact true savings, and checkout budget into a standard spreadsheet or plaintext summary file.