KithfulHere’s the problem I kept running into. A yellow tag says SALE, and I have no idea what the item cost last month. At Ruler Foods, IGA and Dollar General, the same cereal can be a different price on a different week, and the tag never says what “regular” means. If I can’t remember what I paid, the sale tag is just a guess with a color.
I built Kithful, so this post leans on how I ended up solving it. But most of it works with a pen and a notebook, and I’ll say where that’s enough.
What to write down
A price on its own tells you almost nothing. Track these four things:
| Field | Why it matters |
|---|---|
| Item | Keep the name the same each time, or you can’t find the old price |
| Size | A 12 oz box and a 16 oz box are not the same product |
| Price paid | What came off your receipt, not the shelf tag |
| Store | The same box can differ a lot between two stores |
Add the date if you can. Everything else, like cashier numbers and tax codes, can go.
Why unit price beats shelf price
A smaller package that is cheaper on the tag can cost more per ounce. Here is a made-up example, in dollars:
| Package | Price | Price per fl oz |
|---|---|---|
| Half gallon of milk (64 fl oz) | 2.29 | 0.036 |
| Gallon of milk (128 fl oz) | 3.99 | 0.031 |
The half gallon looks cheaper on the tag. The gallon costs less for every ounce. That’s why a tracker that only compares tags will tell you the wrong thing when a brand shrinks a box or you switch sizes.
If you track by hand, add one column: price divided by the size. A phone calculator does it in a few seconds.
Find your “usual” price
Your usual price is the one you could name without looking. Two habits make it honest.
Use the middle, not the lowest. If the last five prices you paid were 3.29, 3.29, 3.49, 2.19 and 3.39, your usual is 3.29. The 2.19 was a clearance buy. If you call 2.19 normal, every regular price looks like a rip-off, and real sales stop standing out.
Only compare the same size. Mixing a gallon and a half gallon into one average gives you a number that matches neither.
Where the prices come from
You have three choices, from least to most work.
- A notebook or notes app. It works for the five things you buy every week. It fails the week you’re tired, and that’s most weeks.
- A spreadsheet. Good if you like spreadsheets. Typing in a receipt of 30 items takes longer than the trip itself did. A price book is a real old habit, and people who keep one do know their prices.
- Your receipts. They already hold the name, size, price and store. The work is getting them out. Take a photo of the receipt the day you shop, while the print is dark. I wrote up how receipt scanning works, and what goes wrong with it, because store shorthand like “KRO DLX SHELLS N C” trips up most scanners.
Tip: Whichever you pick, compare one thing first. Choose five items you buy nearly every week, like milk, eggs, bread, cheese and cereal. Track only those for a month. You’ll know more about your own prices than any list of national averages could tell you.
How to spot a real sale
Once you know your usual price, a sale is easy to judge. Ask three questions:
- Is the sale price below your usual, per ounce?
- Is it the same product and size you buy, not a lookalike?
- Do you have room to store it? A sale on something that goes bad in a week is not a deal if half of it gets thrown out.
Sale lines on receipts also read differently from store to store. At Dollar General an item prints at the shelf price and a “less promo” line comes off it. At our IGA the item prints at the price you already paid, and the “Markdown” line only tells you how much you saved. If you copy prices off a receipt by hand, check which kind you have.
How Kithful does it
Kithful works from receipts, so there’s nothing to type for each item.
- You scan a receipt and check it. Nothing is saved until you confirm the names and prices.
- Each priced line goes into your price history. Open Pantry, then tap Price history. You’ll see each item with every price you paid, the size, the store and the date, newest first, with an arrow showing up or down from last time.
- Sizes are compared per unit. When two purchases are different sizes of the same thing, it compares price per ounce or per fluid ounce and labels it “different size”. When it can’t tell the sizes, it shows no comparison at all instead of guessing.
- ”Usually” is the middle of your recent prices. Once you’ve bought an item three times at the same size, it uses the middle of up to your last five. With fewer than three, it shows the last price you paid.
- Sales show up beside your usual price. If something you’re low on is in this week’s ad at a store you picked, the list and the Today screen show the sale next to what you usually pay, plus a coupon from your wallet if you have one. You can read more in the grocery list with deals guide, and how to set a list up by store.
Two things keep it trustworthy. Items only count as the same product if they share a barcode or you’ve confirmed they match. It never merges look-alike names on its own guess. And a sale only appears beside an item after a check that it’s the same product.
What it doesn’t do: it doesn’t track prices at stores you don’t shop, it doesn’t send price alerts, and it has no chart. Price history is a plain list. Items you add by typing or by barcode have no price, so they won’t appear until a receipt carries one. If a receipt line is faded or unreadable, you type the price in.
What it costs
Kithful is free, with every feature, for the whole family. The free plan includes 30 photo scans a month, and a receipt counts as one scan however many photos it takes. Kithful Plus is unlimited scans for $4.99 a month or $39.99 a year, one price for the household. Kithful is invite-only right now; you can ask for early access on the home page.
Price tracking doesn’t need to be a hobby. Pick five items, keep the size and store with each price, and compare per ounce. A month later, the yellow tags start to mean something.