The same dollar amount can be framed to feel like a bargain or a splurge purely by changing what you divide it by. Supplement marketing knows this, and the choice of denominator is rarely an accident. The two most common frames are per bottle and per day, and they pull in opposite directions.
A per-day frame makes a product feel almost free. Less than a dollar a day sounds trivial, easier than skipping it. But a dollar a day is three hundred sixty-five dollars a year, and across a cabinet of several products that framing quietly adds up to a number you would never have agreed to as a lump sum. The per-day frame works by making the total invisible.
A per-bottle frame does the reverse. A sixty dollar bottle sounds like a lot until you learn it lasts four months, at which point the per-day cost is about fifty cents. Sellers reach for the per-bottle frame when a product is cheap per day but has an intimidating sticker, and for the per-day frame when the sticker is friendly but the long-run cost is high.
The defense is to always compute both and look at them together. Take the price, the servings per container, and your intended servings per day. From those you get cost per day, days per bottle, and annual cost. Whichever single number a page is showing you, derive the other two yourself, because the page chose its number to steer you.
Pay special attention when the per-day number is paired with a subscription. Per day framing plus auto-renewal is the combination most likely to make a recurring annual cost feel like a small daily habit. Neither framing is dishonest on its own, but together they are engineered to keep the yearly total out of view.
Run a quick example. A product framed at sixty-six cents a day with a ninety-day bottle is a sixty dollar charge every three months, roughly two hundred forty dollars a year. Seeing all three numbers at once is the only way to react to the price you are actually paying rather than the one the page picked to show you.