Store Brand vs Name Brand Calculator: Grocery Savings

How the store-brand math works

Three numbers decide the saving. The weekly spend is the size of the bill. The store-brand share is how much of that bill is store brand. The price gap is how much cheaper the store brand is. Multiply all three: $150.00 times 50% times 25% is $18.75 a week. The yearly saving is the weekly saving times 52 weeks: $18.75 times 52 is $975.00. The 5-year saving is the yearly saving times 5: $975.00 times 5 is $4,875.00. The whole-basket discount is the share times the gap: 50% times 25% is 12.50% — because only half the basket gets the 25% discount, the basket as a whole is 12.50% cheaper. Raise the share and the saving rises in proportion; raise the gap and it rises the same way.

The worked example, line by line

Setup: weekly spend $150.00, store-brand share 50%, price gap 25%.

Line 1 — weekly savings. $150.00 × 50% × 25% = $150.00 × 0.50 × 0.25 = $18.75.

Line 2 — annual savings. $18.75 × 52 weeks = $975.00.

Line 3 — 5-year savings. $975.00 × 5 = $4,875.00.

Line 4 — whole-basket discount. 50% × 25% = 12.50% off the whole basket.

Branch — 100% store brand: $150.00 × 100% × 25% = $37.50 a week, $1,950.00 a year.

Branch — 25% share: $150.00 × 25% × 25% = $9.38 a week (the exact figure is $9.375, rounded to cents), $487.50 a year.

Branch — 40% gap: $150.00 × 50% × 40% = $30.00 a week, $1,560.00 a year.

Branch — $100 a week: $100.00 × 50% × 25% = $12.50 a week, $650.00 a year.

Every branch, checked

100% store brand: every item in the basket is store brand, so the full 25% gap applies to the whole $150.00 — $37.50 a week, $1,950.00 a year, $9,750.00 over 5 years. That is the ceiling at this gap: double the share, double the saving.

25% store brand: only a quarter of the basket is store brand, so the saving halves from the default — $9.38 a week (exactly $9.375, rounded to cents) and $487.50 a year. Even a quarter of the basket switched is worth nearly $500.00 a year.

40% price gap: the store brand is 40% cheaper instead of 25%, so the saving rises to $30.00 a week and $1,560.00 a year. Big gaps like this are common on paper goods and pantry staples, where the name brand charges most for the label.

$100 a week of groceries: a smaller shop scales the saving down in proportion — $12.50 a week and $650.00 a year at the same share and gap. The saving is a percentage of the spend, so a bigger shop saves more in dollars and exactly the same in percent.

The honest flip: the name brand on sale

There is exactly one realistic way the name brand wins on price, and it is a sale. Take a $10.00 item. The store brand at a 25% gap costs $7.50. The name brand on a 30% sale costs $7.00. The name brand wins by $0.50. The flip rule is simple: buy the name brand when its sale price drops below the store-brand price — 30% off a $10.00 name brand is $7.00, which is less than the $7.50 store brand, so the sale wins. At the usual 20–30% gap, any sale deeper than the gap flips that item. The practical habit is to check the sale price per item, not per basket: buy the store brand where there is no sale, and the name brand where the sale beats it.

The 20–30% gap, and where it comes from

Industry surveys typically put store-brand savings at 20–30% against the name brand — that is the range this page uses for its default, and it is a range, not a promise. The gap is widest on pantry staples, paper goods, and canned goods, where the product is close to a commodity and the name brand's price is mostly the label, the advertising, and the shelf position. It is narrowest where the recipe matters — a sauce, a coffee, a cereal — and where the name brand's formula is genuinely different. The gap also varies by store: discount chains run narrower gaps because their name brands are already cheap, while premium chains run wider ones. The 25% default sits in the middle of the typical range; enter the gap from your own shelf if you know it — a $10.00 name brand against a $7.50 store brand is exactly a 25% gap, and that is the number to measure.

Where store brand usually wins — and where it does not

Store brand usually wins on the boring items: flour, sugar, salt, canned beans, pasta, rice, paper towels, cleaning sprays — products where the recipe is standard and the label is the main difference. It wins less often where taste is the product: a coffee blend, a chocolate, a salad dressing, a cheese — there the name brand's recipe can be genuinely different, and a store brand you do not enjoy is not a saving, it is waste. The honest test is one item at a time: switch the staples first, where the gap is widest and the risk is lowest, and keep the name brand where you can taste the difference. A household that switches half the basket — the default on this page — usually finds the staples switch easily and a few favourites stay name brand, which is exactly why the default share is 50% and not 100%.

Rounding convention, stated plainly: each dollar total is rounded to cents, and the yearly total is the unrounded weekly saving times 52 — so the 25% share branch shows $9.38 a week (the exact figure is $9.375) and $487.50 a year ($9.375 times 52). The 5-year total is the yearly total times 5. Percentages are shown to two decimals: 50% times 25% is exactly 12.50%.

Output · formula · meaning

Who uses this

• The weekly shopper: spends $150.00 a week, buys half as store brand, and learns the saving is $18.75 a week — $975.00 a year and $4,875.00 over 5 years, a 12.50% discount on the whole basket.
• The full switcher: buys everything as store brand and learns the saving doubles to $37.50 a week and $1,950.00 a year — and that the ceiling at a 25% gap is exactly a quarter of the weekly spend.
• The sale hunter: watches the sale shelf and learns the flip rule — a name brand on a 30% sale costs $7.00 against a $7.50 store brand, so the sale wins by $0.50 on a $10.00 item.
• The small-shop saver: spends $100.00 a week and learns the saving is still $12.50 a week and $650.00 a year at the same share and gap — a percentage of the spend, so a smaller shop saves less in dollars and exactly the same in percent.

Accuracy & limitations

The math is exact for the numbers you enter: weekly savings is spend times share times gap, annual is weekly times 52, and 5-year is annual times 5. But the inputs carry the assumptions. The 25% gap is a typical figure — industry surveys typically put store-brand savings at 20–30% — and the real gap varies by item, by store, and by week: a store brand that is 40% cheaper on paper towels can be only 10% cheaper on coffee. The share is your estimate of how much of the basket you actually switch; a 50% share assumes the staples switch and the favourites stay name brand. The model assumes the gap stays the same all year — sales, coupons, and loyalty prices move both sides week to week, and the flip rule is the way to handle that: compare the sale price against the store-brand price item by item. It also assumes the store brand is a like-for-like swap — if the store brand is smaller, weaker, or wasted because nobody likes it, the saving is not real. This page compares shelf prices, not nutrition or quality — check the label and your own taste before switching a favourite.