Grocery Intelligence

How We Detect Real Half-Price Grocery Deals

Cutting through supermarket pricing tricks to surface genuine 50% off deals from Coles and Woolworths — backed by historical data, not marketing labels.

Every week, Australian supermarkets advertise thousands of “specials.” Bright tags, crossed-out prices, and urgent messaging suggest massive savings — yet many of these discounts are little more than clever price anchoring.

Our Grocery Deals system was built to answer one question with precision: is this actually half price?

The Problem with Supermarket “Specials”

Promotional pricing often relies on short-lived reference prices. An item’s price may be temporarily inflated, then “discounted” back to its normal level — creating the illusion of savings where none exist.

  • Fake discounts: “Was” prices that don’t reflect normal selling levels
  • Shallow promotions: 10–20% cuts framed as major specials
  • Promotion cycling: The same products rotating every few weeks

Key principle: A deal is only real if it is meaningfully cheaper than its long-term price — not last week’s marketing anchor.

Price History Is the Source of Truth

Instead of trusting advertised discounts, our system tracks how products are priced week after week across Coles and Woolworths.

  • Baseline price: The most common selling price over time
  • Discount depth: Deviation from the true baseline
  • Promotion frequency: How often a product is discounted

Only deals that meet strict thresholds — including a genuine ~50% reduction from normal pricing — are surfaced as half-price specials.

Coles vs Woolworths: Continuous Comparison

Identical products often carry different prices across supermarkets. Our system continuously compares both retailers to reveal where the real savings exist each week.

  • Asymmetric promotions between retailers
  • Different discount depths on the same product
  • Identifying the consistently cheaper seller

Example: A pantry staple discounted at Woolworths one week frequently appears at Coles the following week — but not always at the same depth or value.

How the Deal Detection Works

  1. 1Collect: Weekly pricing data from major supermarkets
  2. 2Normalize: Clean SKUs, pack sizes, and unit pricing
  3. 3Baseline: Establish normal selling prices over time
  4. 4Filter: Detect genuine ~50% deviations
  5. 5Rank: Surface the strongest value deals first

The result is a transparent, data-backed list of real savings — free from promotional noise.

Who This Is Built For

  • Families: Reduce weekly grocery spend without extra planning
  • Cost-conscious shoppers: Avoid misleading specials
  • Bulk buyers: Know exactly when to stock up
  • Data-driven consumers: Prefer transparency over hype

Start Saving Smarter

Grocery prices aren’t going down — but overpaying is optional. Our Grocery Deals Tracker shows where real half-price savings actually exist, updated every week.

Try it now: Open the Grocery Deals App