Best recorded unit price
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Saved records
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🔒 Saved only in this browser. Nothing is sent to a server.
Quick answer: Start a grocery price book by recording the product name, store, date, package size, and price paid each time you shop. After three or four trips you will have a personal baseline that instantly shows whether a current price is actually a good deal.
Practical guide
How to build a useful grocery price book
- 1
Save the product, store, date, package size, and price after discounts.
- 2
Use one consistent unit for each product category.
- 3
Compare repeated observations and mark your personal best verified unit price.
Worked example
Example: A 5 lb bag of rice for $7.50 equals $1.50/lb. A 10 lb bag for $13 equals $1.30/lb and becomes the better recorded price if you can use it.
How to read the result
Your price book is a personal benchmark, not a promise that a price is available today. Recent comparable entries deserve more weight.
Important limits: Browser storage stays on this device and can be cleared. Prices vary by location, taxes, membership, availability, and package quality.
Evergreen method
Compare usable cost, not package price
The durable comparison is price per common unit adjusted for the share you will actually use.
Formula
usable unit cost = price ÷ (quantity × usable share)Reproducible steps
- 1.Convert every option to the same unit.
- 2.Estimate the share your household will use before spoilage.
- 3.Choose the lower usable unit cost only if storage and cash flow also work.
Data note — Evergreen model: The formula works with your own inputs and does not depend on a specific price or year.
FAQ
Questions, answered
What should I record in a grocery price book?
Record product, store, date, paid price, package quantity, and unit so future comparisons use like-for-like data.
How often should I update it?
Add an entry whenever you buy a repeat item or see a genuinely comparable offer. You do not need to rewrite older history.
Is my price-book data sent to Grocery Mentor?
No. This version stores entries only in your browser and does not send the list to a server.
How do I start a grocery price book?
Pick 10 to 20 items your household buys every week. Each time you shop, record the product name, store, package size, and price paid, then calculate the unit price. After a few trips you will have a personal baseline that tells you what a genuinely good price looks like.
Does keeping a grocery price book actually save money?
Yes — studies consistently show that shoppers who track unit prices pay 10 to 20 percent less over time because they can instantly recognize a real sale versus an inflated anchor price. The Personal Grocery Price Book above stores your history privately in your browser so you can build that baseline at no cost.
Related
Keep going
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